Chemistry & Earth Sciences: Recent submissions
Now showing items 121-140 of 600
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Crosslinked chitosan–montmorillonite composite and its magnetized counterpart for the removal of basic fuchsin from wastewater: Parametric optimization using Box-Behnken design
( Elsevier , 2024 , Article)Treating wastewater polluted with organic dyestuffs is still a challenge. In that vein, facile synthesis of a structurally simple composite of chitosan with montmorillonite (CS-MMT) using glutaraldehyde as a crosslinker ... -
Application of Pineapple Leaves as Adsorbents for Removal of Rose Bengal from Wastewater: Process Optimization Operating Face-Centered Central Composite Design (FCCCD)
( Multidisciplinary Digital Publishing Institute (MDPI) , 2020 , Article)Adsorptive removal of rose bengal (RB) from contaminated water samples was approached using pineapple leaves (PAL). Three adsorbents were utilized for that purpose; raw pineapple leaves (RPAL) and the thermally activated ... -
Eco-structured adsorptive removal of tigecycline from wastewater: Date pits’ biochar versus the magnetic biochar
( Multidisciplinary Digital Publishing Institute (MDPI) , 2020 , Article)Non-magnetic and magnetic low-cost biochar (BC) from date pits (DP) were applied to remove tigecycline (TIGC) from TIGC-artificially contaminated water samples. Pristine biochar from DP (BCDP) and magnetite-decorated biochar ... -
Constituents of plants growing in Qatar - Part XIX. Flavonoids of Glossonema edule N. E. Br.
( Springer Nature , 1990 , Article)The study of the flavonoids of the unripe fruits of Glossonema edule, resulted in the isolation and identification of apigenin 6,8-di-C-glucoside (violanthin) and luteolin 7-O-glucoside. © 1990 Kluwer Academic Publishers. -
Constituents of plants growing in Qatar XX. Phytochemical investigation of anastatica hierochuntica: NOTE
( Taylor & Francis , 1993 , Article)A study of the lipid fraction of Anastatica hierochuntica (Cruciferae) resulted in the isolation of hydrocarbon (mainly C25H52, C29H60 AND C31H64) AND sterol fractions (P-sitosterol, campesterol, stigmasterol AND cholesterol). ... -
Constituents of plants growing in Qatar part XV. Chemical investigation and pharmacotoxicity of pyrrolizidine alkaloids of moltikiopsis ciliata
( Taylor & Francis , 1988 , Article)Chemical study of the alkaloidal constituents of Moltikiopsis ciliata resulted in the isolation and identification of heliotrine and echinatine, in addition to other minor alkaloids. Pharmacological experiments revealed: ... -
Constituents of plants growing in Qatar VII an examination of certain plants for anti-inflammatory activity
( Taylor & Francis , 1985 , Article)Six desert plants native to the State of Qatar were successively extracted with hexane, chloroform and ethanol. These extracts were examined for their ability to inhibit aggregation of rabbit blood platelets induced by ... -
Constituents of plants growing in Qatar
( Elsevier , 1986 , Article)N/A. -
Novel potentiometric copper (II) selective membrane sensors based on cyclic tetrapeptide derivatives as neutral ionophores
( Elsevier , 2005 , Article)Two novel membrane sensors sensitive and reasonably selective for Cu2+ ions are described. These are based on the use of newly synthesized cyclic tetrapeptide derivatives as neutral ionophores and sodium tetraphenylborate ... -
Solid-state planar microsensors for selective potentiometric determination of ethylmorphine
( Marcel Dekker Inc. , 1999 , Article)The potentiometric performance characteristics of microelectronically fabricated solid-state planar ethylmorphine sensors based on silicon/silicon nitride substrate and a mixture of ethylmorphine-tetraphenylborate and ... -
Spectrophotometric Determination of Hydrogen Peroxide by a Hydroquinone-Aniline System Catalyzed by Molybdate
( Korean Chemical Society , 2004 , Article)In this system hydroquinone is oxidized to pbenzoquinone by H2O2. 2 aniline are added, in successive stages, to pbenzoquinone, to yield the disubstituted quinone as the final product. 20 The UV-VIS spectrum of the product ... -
Constituents of plants growing in qatar V. Constituents of the volatile oil of cymbopogon parkeri
( Elsevier , 1983 , Article)Analysis of the volatile oil of Cymbopogon parkeri has been carried out by capillary gas chromatography-mass spectrometry. To facilitate identification, prefractionation of the oil by adsorption high-performance liquid ... -
Sesquiterpene lactones from Pulicaria sicula
( Elsevier , 1988 , Article)The aerial parts of Pulicaria sicula afforded the known xanthanolides 1-6, the guaianolides 7 and 8 as well as two new ones, the lactone 9 and the corresponding epoxide 10. Furthermore nerylisobutyrate and the thymol ... -
Poisonous plants contaminating edible ones and toxic substances in plant foods IV. Phytochemistry and toxicity of lolium temulentum
( Taylor & Francis , 2008 , Article)Different procedures were carried out for the preparation and separation of the total alkaloids of Lolium temulentum. Loline has been identified as the major pyrrolizidine alkaloid of the seeds. The toxicity of the alcoholic ... -
Constituents of plants growing in Qatar IX. The antispasmodic components of cymbopogon parkeri stapf. Parkeri stapf
( Taylor & Francis , 1986 , Article)Investigation of the lipid fraction of Cymbopogon parkeri revealed the presence of several active constituents, one of which possesses an antispasmodic activity and was identified as cryptomeridiol. Study of the other ... -
Poly(vinyl chloride) matrix membrane electrodes for manual and flow injection determination of metal azides
( The Royal Society of Chemistry , 1992 , Article)Novel poly(vinyl chloride) matrix membrane electrodes for the azide ion are developed, electrochemically evaluated and used for manual and flow injection determinations of soluble and insoluble metal azides. These electrodes ... -
Continuous potentiometric monitoring of viagra (sildenafil) in pharmaceutical preparations using novel membrane sensors
( Springer Nature , 2006 , Article)Two potentiometric sensors responsive to sildenafil citrate (SC) drug (the active component of viagra) are described, characterized, compared and used for drug assessment. The sensors are based on the use of the ion-association ... -
Nitron tetrachloroaurate(III) electrodes with poly(vinyl chloride) and liquid membranes for the selective determination of gold
( Elsevier , 1991 , Article)PVC matrix and liquid membrane electrodes have been developed for direct potentiometric determination of gold(III). The membranes incorporate nitron tetrachloroaurate(III) as electroactive material. Fast response for ... -
Determination of amitriptyline, imipramine and orphenadrine in antidepressant drugs by potentiometry, spectrophotometry and atomic absorption spectrometry
( Springer-Verlag , 1993 , Article)Methods are described for the determination of amitriptyline, imipramine and orphenadrine in some antidepressant drugs. They are based on a prior reaction with ammonium reineckate to form 1∶1 water-insoluble drugreineckate ...
