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Abstract  

The radiochemical separation of no-carrier-added cerium from proton irradiated lanthanum was studied by solvent extraction using DEE, TBP and TPPO, the latter reagent being employed for the first time for separation of radiocerium from bulk of lanthanum. Distribution coefficients of cerium and lanthanum were investigated as a function of equilibrium time and concentration of HNO3. A mixture of 0.05M K2Cr2O7 and 0.1M H2SO4 was used as an oxidizing agent to improve the separation efficiency of cerium. A comparative study of the three extractants released that DEE is the best for separation of cerium from bulk of lanthanum oxide. The target was prepared by pressing. The production of 139Ce of high radionuclidic purity and chemical purity via irradiation of lanthanum oxide target at MGC-20 cyclotron with protons of energy 14.5 MeV is described. The experimental yield was found to be 153 kBq/μA·h.

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Abstract  

The diamide N,N,N,N′-tetraoctyldiglycolamide (TODGA) was synthesized and characterized. The prepared TODGA was applied for extraction of Ce(III) from nitric acid solutions. The equilibrium studies included the dependencies of cerium distribution ratio on nitric acid, TODGA, nitrate ion, hydrogen ion and cerous ion concentrations. Analysis of the results indicates that the main extracted species is Ce(TODGA)2(NO3)3HNO3. The capacity of Ce loading is approximately 45 mmol/L for 0.1 M solution of TODGA in n-hexane. Finally, the thermodynamic parameters were calculated: K (25 °C) = 3.8 × 103, ΔH = −36.7 ± 1.0 kJ/mol, ΔS = −54.6 ± 3.0 J/K mol, and ΔG = −20.4 ± 0.1 kJ/mol.

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The induction of resistance to charcoal rot disease caused by Macrophomina phaseolina (Tassi) Goidanich in sunflower (Helianthus annuus L.) was studied after seed treatments with coumarin (COU) and salicylic acid (SA) at three different levels (0.3, 1.0 and 3.0 mM). The priming of sunflower seeds with 0.3 mM COU or 1.0 mM SA resulted in decreased disease severity and offered about 50% protection and more than 80% reduction in the length of stem lesions under greenhouse conditions. Both COU and SA treatments induced the accumulation of soluble sugars and phytoalexins, as well as stimulating the activity of β-1,3-glucanase and chitinase.

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Summary

Reversed phase high-performance liquid chromatography (RP-HPLC) and thin-layer chromatography (TLC)-spectrodensitometric methods have been developed and validated for the separation and quantitation of two binary mixtures: Ofloxacin (OFX) and dexamethasone (DXM) in eye preparation; ciprofloxacin hydrochloride (CIP) and hydrocortisone (HYD) in ear preparation. The linearity ranges of RP-HPLC methods were found to be (2.5–45 μg mL−1) for OFX, (2.5–50 μg mL−1) for DXM and (1–8 μg mL−1) for both CIP and HYD. The percentage recoveries/relative standard deviation (RSD) were found to be 100.36/1.38, 100.13/1.49, 99.98/0.61 and 100.28/1.27, respectively. The linearity ranges of TLC-spectrodensitometric methods were found to be (0.5–2 μg band−1), (0.5–3.5 μg band−1), (0.2–1.6 μg band−1), and (0.6–2 μg band−1) for OFX, DXM, CIP, and HYD, respectively. The percentage recoveries/RSD were found to be 99.98/1.06, 99.93/1.18, 99.74/1.27, and 99.94/1.54, respectively. A comparative study was conducted to show the advantages of the proposed methods which showed that the TLC-spectrodensitometric methods were simpler, more sensitive, and economic, while RP-HPLC methods were more precise and robust. The methods were validated in compliance with the ICH guidelines and were successfully applied for determination of the selected drugs in their laboratory-prepared mixtures and commercial dosage forms.

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Abstract  

The radiochemical separation of no-carrier-added zirconium from proton irradiated yttrium was studied by two techniques, namely, ion-exchange chromatography using Dowex 50W-X8 and Dowex 21K resins, and solvent extraction using HDEHP and TPPO, the latter reagent being employed for the first time for separation of radiozirconium from bulk of yttrium. Out of all those techniques, the solvent extraction using TPPO was found to be the best: the separation yield of radiozirconium was >97%, the time of separation was short, the contamination from the long-lived 88Y activity was low (10−4%) and the final product was obtained in the form of oxalate. The production of 89Zr and 88Zr of high radionuclidic and chemical purity via irradiation of yttrium targets with protons of energies 12 and 20 MeV, respectively, is described. The experimental yields of the two radionuclides were found to be 28 MBq/μA·h and 1.63 MBq/μA·h, respectively. Each value corresponds to about 80% of the respective theoretical yield.

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This study investigated the diagnostic value of soluble urokinase plasminogen activator receptor (suPAR) and serum lactate in elderly patients with sepsis and evaluated their capacity to predict mortality and their correlation to Sequential Organ Failure Assessment (SOFA) score. The study included 80 participants, divided into two groups: 40 cases (mean age, 68.9 ± 5.9) admitted to the intensive care unit and 40 healthy controls (mean age, 67.1 ± 6.2). Elderly patients with sepsis had significantly higher levels of serum suPAR and lactic acid compared to healthy controls. Receiver operating characteristic (ROC) curve analysis showed that suPAR (cutoff value, ≥4.37 ng/ml) has higher area under the curve (AUC) than lactic acid (cutoff value, ≥1.95 mmol/l) for diagnosing sepsis. Serum lactate has superior prognostic value compared to suPAR with AUC of 0.82 (cutoff value, 2.2 mmol/l) and 0.72 (cutoff value, 6.3 ng/ml), respectively. The diagnostic power of combined usage of suPAR and lactate serum concentrations showed AUC of 0.988 (95% confidence interval 0.934 to 1.0). The combination of both biomarkers either together or with SOFA score may serve as a useful guide to patients who need more intensive resuscitation.

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This work presents a comparative study on the development and validation of two analytical techniques applied for the simultaneous determination of hydrocortisone acetate (HCA), fusidic acid (FSA), methyl paraben (MPB), and propyl paraben (PPB) formulated as a topical cream. The first technique was thin-layer chromatography (TLC)–densitometric method, which was developed by separating the four components on silica gel 60 F254 using methylene chloride–methanol–benzene in the ratio of 10:2:5, v/v, as the developing system, followed by densitometric measurement of the bands at 240 nm. The second technique was the chemometric method using two models: principle component regression model (PCR) and partial least squares (PLS). The suggested techniques were validated in compliance with the International Conference on Harmonization (ICH) guidelines and were successfully applied for the determination of the quaternary mixtures as prepared synthetically in laboratory and in the commercial topical pharmaceutical formulation.

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Abstract

In this study, the mineralogical content of Abu Rusheid mylonite sample was investigated and revealed that the sample is essentially composed of quartz and feldspar (72.14% mass), muscovite (16.6% mass), and contains heavy economic polymetallic minerals of about 2.65% by mass. By studying the differences in the physical properties of this mineral content, a proposed flow sheet was set up to explain the successive physical upgrading steps for concentrating and separating the valuable minerals content and getting rid of the associated gangue minerals. Industrial, economic and strategic polymetallic minerals were identified at Abu Rusheid mylonite sample, including cassiterite, titanite, brass, kasolite, monazite, and uranothorite. A group of sulfide minerals also existed as pyrite, arsenopyrite, galena, and molybdenite in addition to the presence of fluorite and iron oxides bearing rare earth elements (REEs) and base metals. Using dry high intensity magnetic separation followed by wet gravity separation and flotation, three concentrates were obtained; heavy paramagnetic concentrate (monazite, columbite, brass, and jarosite), heavy diamagnetic concentrate (zircon, kasolite, uranothorite, cassiterite, and sulphide minerals) and muscovite concentrate for industrial uses. Physical processing of Abu Rusheid mylonite sample was carried out to produce high grade mineral concentrate used as a raw material for chemical treatment to extract economic elements that necessary for several industries.

Open access
JPC - Journal of Planar Chromatography - Modern TLC
Authors:
Omer A. Basudan
,
Perwez Alam
,
Nasir A. Siddiqui
,
Mohamed F. Alajmi
,
Adnan J. Alrehaily
,
Saleh I. Alqasoumi
,
Maged S. Abdel-Kader
,
Prawez Alam
, and
Abd El Raheim M. Donia

A simple and sensitive high-performance thin-layer chromatographic (HPTLC) method was developed for the evaluation of biomarker β-amyrin in the leaves of fve different species of genus Ficus (Ficus carica, Ficus nitida, Ficus ingens, Ficus palmata, and Ficus vasta) grown in the Kingdom of Saudi Arabia. Chromatography was performed on glass-backed silica gel 60 F254 HPTLC plates with solvents toluene–methanol (9:1, v/v) as the mobile phase. After development, the HPTLC plate was derivatized with p-anisalde-hydereagent to give well-resolved and compact spot of β-amyrin. Scanning and quantifcation were done at 550 nm. The system was found to give compact spot for β-amyrin at R F = 0.58. The linear regression analysis data for the calibration plots showed good linear relationship with r 2 = 0.998 with respect to area in the concentration range of 100–900 ng. The regression equation for β-amyrin standard was found to be Y = 5.835X + 87. The precisions (n = 6) for β-amyrin were found to be 1.64–1.77% and 1.68–1.84%, respectively, for intra-day and inter-day batches, and the recovery values were found to be 97.6–98.3%. β-Amyrin was found to be present in three species, i.e., F. carica (0.29%, w/w), F. nitida (0. 5 4% w/w), and F. p almata (0.31%, w/w), while it was absent in F. vasta and F. ingens. The statistical analysis proves that the developed method for the quantifcation of β-amyrin is reproducible; hence, it can beemployed for the determination of β-amyrin in plasma and other biological fuids as well as in fnished products avai lable in the market.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
N. Shinohara
,
Y. Hatsukawa
,
K. Hata
,
N. Kohno
,
M. Andoh
,
H. Saleh
,
W. Charlton
,
T. Parish
, and
S. Raman

Abstract  

For nuclear transmutation of minor actinides, delayed neutron emission measurement for241Am was carried out in thermal neutron irradiation location. The neutron capture cross sections of241Am were also measured radiochemically. The transmutation process of241Am in reactor is discussed by calculating the yields of minor actinides with the nuclear data measured in this study and the evaluated values. The accelerator driven transmutation of minor actinides by high-flux neutrons from spallation reactions is also presented.

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