Chemistry & Earth Sciences: Recent submissions
Now showing items 561-580 of 587
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Kinetics and mechanism of H2O2 decomposition by Cu(II)-, Co(II)-, and Fe(III)-Amine complexes on the surface of Silica-Alumina (25% Al2O3)
( John Wiley & Sons, Inc. , 1994 , Article)The kinetics of the H2O2 decomposition by Cu(II)-, Co(II)-, and Fe(III)-amine complexes supported on the surface of silica-alumina (25% Al2O3) catalyst have been investigated. The decomposition process proceeded with ... -
REMOTE MONITORING AND CONTROL OF MICROCOMPUTER RAISED DATA ACQUISITION SYSTEMS
( Blackwell Publishing Ltd , 1994 , Article) -
Possible evidence for the existence of a hairy layer at the surface of polymer latex particles
( John Wiley & Sons, Ltd. , 1998 , Article)In this work, an attempt is made to verify the existence of a hairy layer at the surface of polymer latex particles, and determine its thickness under different conditions. Two systems have been studied. In one system, ... -
Optical and electrical properties of a new polymer
( John Wiley & Sons, Inc. , 1997 , Article)Thin film of poly (5-isopropylidenecyclo-1,4-vinylene-2,3-dicarboxylicacidamide-s-methyl hydrazinecarbodithioate) (II) (Scheme 1) of 5 μm thickness was prepared. The dielectric properties of the prepared sample were studied ... -
Evidence for some prostaglandins in Allium sativum extracts
( John Wiley & Sons, Ltd. , 1988 , Article)Homogenized garlic (Allium sativum Linn.) was extracted successively with organic solvents and the prostaglandin-rich fraction separated. Fractionation of the extract with column chromatography was performed. TLC of the ... -
Ground- and excited-state properties of some 3,4-dihydro-1-(2-p-substituted benzylidene)naphthalenones: substituent and environmental effects
( John Wiley & Sons, Ltd. , 1997 , Article)Electronic absorption and steady-state fluorescence emission of seven 3,4-dihydro-1-(2-p-substituted benzylidene)naphthalenones (1–7) show sizable solvent dependence. The charge-transfer (CT) absorption maxima of these ... -
Mercury pollution in doha (Qatar) coastal environment
( Wiley Periodicals, Inc. , 1994 , Article)Surface water and sediment samples were collected from the Doha coastal area and analyzed for content of physico-chemical forms of mercury. Dissolved reactive Hg (2.9 ng L?1) represented 81.0% of the total dissolved Hg ... -
TiO2 nanotubes with ultrathin walls for enhanced water splitting
( Royal Society of Chemistry , 2015 , Article)We demonstrate, for the first time, the synthesis of titania nanotubes with ultrathin (3–5 nm) wall thickness. As revealed by the incident photon-to-current collection efficiency (IPCE) and electrochemical impedance ... -
Hazards influencing coastal plains management along the Eastern stretch of the Gulf of Suez, Using remote sensing and GIS
( IEEE , 2008 , Conference Paper)This research aims at to assess the impact of natural hazards on the human activities and development planning held along the eastern coastal stretch of the Gulf of Suez. Change detection technique was used in combined ... -
Water resources assessment at El-Arish area, using remote sensing and GIS, North Sinai, Egypt
( IEEE , 2008 , Conference Paper)This research aims at to analyse the pattern and rate of shoreline changes at the El-Arish area during the period 1984-2006, which represents the time at which the El-Arish harbour has affected along the coastline. Detecting ... -
Geology and petrology of the Hormuz dolomite, Infra-Cambrian: Implications for the formation of the salt-cored Halul and Shraouh islands, Offshore, State of Qatar
( Elsevier Ltd , 2008 , Article)Geological investigations of the Halul and the Shraouh islands, offshore Qatar, indicate that most of their calcareous rocks, which display abundant stromatolitic bedding, belong to the Infra-Cambrian Hormuz Series. ... -
Bordetella pertussis risA, but not risS, is required for maximal expression of Bvg-repressed genes
( American Society for Microbiology , 2005 , Article)Expression of virulence determinants by Bordetella pertussis, the primary etiological agent of whooping cough, is regulated by the BvgAS two-component regulatory system. The role of a second two-component regulatory system, ... -
Spectroscopic investigation of the donor-acceptor interaction between o-phenylenediamine and tetracyanoethylene in dichloromethane
( Elsevier B. V. , 2007 , Article)The interaction between the electron donor o-phenylenediamine (o-phendn) and the π-acceptor tetracyanoethylene (TCNE) has been investigated spectrophotometrically in dichloromethane at 25 °C. The results indicate that the ... -
Synthesis, spectroscopic and thermal investigations of solid charge-transfer complexes of 1,4,7-trimethyl-1,4,7-triazacyclononane and the acceptors iodine, TCNE, TCNQ and chloranil
( Elsevier , 2008 , Article)The solid charge-transfer complexes formed in the reaction of the electron donor 1,4,7-trimethyl-1,4,7-triazacyclononane (TMTACN) with the acceptors iodine, tetracyanoethylene (TCNE) and 7,7,8,8-tetracyanoquinodimethane ... -
Cobalt phthalocyanine as a novel molecular recognition reagent for batch and flow injection potentiometric and spectrophotometric determination of anionic surfactants
( Elsevier B. V. , 2008 , Article)Cobalt(II) phthalocyanine [Co(II)Pc] is used as both an ionophore and chromogen for batch and flow injection potentiometric and spectrophotometric determination of anionic surfactants (SDS), respectively. The potentiometric ... -
Synthesis, spectroscopic, thermal and structural investigations of charge-transfer complexes of 4,4′-trimethylenedipiperidine with chloranil, TBCHD, DDQ, TCNQ and iodine
( Elsevier , 2009 , Article)The charge-transfer interactions between the electron donor 4,4′-trimethylenedipiperidine (TMDP) and the acceptors 2,3,5,6-tetrachloro-1,4-benzoquinone (chloranil), 2,4,4,6-tetrabromo-2,5-cyclohexadienone (TBCHD), ... -
Functional Overexpression and Purification of a Codon Optimized Synthetic Glucarpidase (Carboxypeptidase G2) in Escherichia coli
( Springer US , 2009 , Article)Glucarpidase (former name: carboxypeptidase G2, or CPG2) is a bacterial enzyme that is widely used in detoxification of the cytotoxic drug, methotrexate, and in Antibody Directed Enzyme Prodrug Therapy for cancer treatment. ... -
Synthesis, spectroscopic and thermal structural investigations of the charge-transfer complexes formed in the reaction of 1-methylpiperidine with σ- and π-acceptors
( Elsevier B.V. , 2009 , Article)The reactions of the electron donor 1-methylpiperidine (1MP) with the π-acceptors 7,7,8,8-tetracyanoquinodimethane (TCNQ), tetracyanoethylene (TCNE), 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), 2,3,5,6-tetrachloro-1,4 ... -
Ab initio study on the formation of triiodide CT complex from the reaction of iodine with 2,3-diaminopyridine
( Elsevier , 2010 , Article)The charge transfer (CT) interaction between iodine and 2,3-diaminopyridine (DAPY) has been thoroughly investigated via theoretical calculations. A Hartree–Fock, 3-21G level of theory was used to optimize and calculate the ... -
Constituents Of Green Beans Phaseolus Vulgaris (Lipids And Flavonoids)
( Qatar University , 1992 , Article)Chemical study of the lipid fraction resulted in the isolation and identification of a hydrocarbon fraction (n-Czg -0-033); an aliphatic alcohol fraction (C^, Czp, €30) and a sterol fraction (stigmasterol and sitosterol). ...