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Effect of Stearic Acid on Ettringite Formation

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Journal of Materials Science & Technology 2002年第3期18卷 263-265页

作者： Essam A.Kishardepartment of chemistry, Faculty of girls, ain shams university, cairo, egypt [ Manuscript received March 29, 2001, in revised form June 11, 2001] Dept. of Chem. Faculty of Girls Ain Shams Univ. Cairo Egypt

The hydration reaction of a mixture of tricalcium aluminate (C3A) and gypsum with the molar ratio of 1:3 was carried out at room temperature and a water/solid ratio of 4.0. The hydration was carried out in presence of 0, 1 and 3% stearic acid and the mixes were designated as A, B and C, respectively. Ettringite was the only hydration product formed in the presence and absence of stearic acid. Phase composition, microstructure, infra-red analysis as well as degree of hydration were carried out for the different hydration mixtures. The rate of ettringite formation in the presence of 3% stearic acid was accelerated during the first half hour of hydration, and then retardation was occurred. In the presence of 1% stearic acid the ettringite formation was accelerated first till 3 days, then retardation was observed at later hydration ages.

关键词： Stearic acid Hydration Ettringite

Condensation of α-and β-acetylnaphthalene with dimethyl β,β-dimethyl glutarate

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Chinese Journal of chemistry 1991年第4期9卷 360-364页

作者： el-BASSIOUNY Fakhry Abdel-Aziz department of chemistry,Faculty of Science,ain shams university,cairo,A.R.egypt

α-and β-Acetylnaphthalenes condensed with dimethyl β,β-dimethyl glutarate in the presence of sodium hydride to give the corresponding half-esters,the E-isomers 2a and 2b being predominant. The structure and config... 详细信息

关键词： Condensation of dimethyl glutarate and acetylnaphthalene with dimethyl

Behaviour of 4-(4-chlorophenyl)-6-(4-tolyl)-4,5-dihydro pyrimidine-2(1H)thione and 2-hydrazino derivative toward carbon electrophiles

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Chinese Journal of chemistry 1991年第2期9卷 189-192页

作者： el-HASHASH,M.A el-KAFRAWY,A.F SHIBA,S.A.Faculty of Science,ain shams university,Abbassia, cairo.egypt Faculty of Science Ain Shams University Abbassia Cairo. Egypt

The reaction of thiourea with p-methyl-β-p-chlorophenyl acrylophenone(1)is,in princi- ple,an attractive[3+ 3]-fragment approach to the synthesis of dihydropyrimidine bearing aryl groups.

关键词： Behaviour of 4 chlorophenyl dihydro pyrimidine-2 thione and 2-hydrazino derivative toward carbon electrophiles tolyl

A novel 2-C reactivity studies of 1-aroyl-l,2dihydro-3H-naphtho[2,1-b]pyran-3-ones

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Chinese Journal of chemistry 1990年第5期8卷 446-450页

作者： el-KASABY,M.A. HASSAN,M.A. SHIBA,S.A. ABOU-el-REGAL,M.M.department of chemistry,Faculty of Science,ain shams university,cairo,egypt

The 2-C,methylene group of 1-aroyl-1,2-dihydro-3H-naphtho[2,1-b]pyran-3-ones (2)have been showed to possess a superior reactivity towards many of organic *** na- phthopyrones(2)condensed with aromatic aldehydes to give the 2-arylidine derivatives(3).Bromin- ation of 2 gave 1,2-dibromo(4)or 5-bromo(5)derivatives depending on the reaction conditions. The base catalyzed addition or cycloaddition of naphthopyrones(2)to 4-methoxy benzalacetophenone gave the expected Michael adduct(6)or the cyclic adducts(7-9)depending on the type of catalytic base and reaction *** of the products have been established by elemental analyses, IR and ~1H NMR spectroscopic methods.

关键词： CDC A novel 2-C reactivity studies of 1-aroyl-l,2dihydro-3H-naphtho[2,1-b]pyran-3-ones 占一

Synthesis and comparative study of reactivities of δ-lactone,estor group and oxazinone ring in coumarin derivatives towards carbon or nitrogen nucleophiles

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Chinese Journal of chemistry 1990年第5期8卷 469-473页

作者： el-KAFRAWY,A.F. SOLIMAN,A.Y. BAKER,H.M. MOHAMED,F.K. el-KADY,M.Y.department of chemistry,Faculty of Science,ain shams university and Faculty of Education at el-Fayoum,cairo.egypt department of chemistry Faculty of Science Ain Shams University and Faculty of Education at El‐Fayoum Cairo Egypt

Condensation of methyl 7-methylcoumarin-4-acetate(2)with primary amines and with an- thranilic acid gave 7-methyl-2-oxo-N-aryl-2H-[1]-benzopyran-4--acetamide(4a—d)and(7),respectively. Compound 7 underwent cyclization to give 2-(7-methyl-2-oxo-2H-[1]-benzopyran-4-yl)-methyl-4H-3,1- benzoxazin-4-one(3).The reaction of 3 with aromatic amines gave the corresponding quinazolone derivatives 5 which tautomerises to the thermodynamically more stable isomer 6,whereas its reaction with Grignard reagents and aromatic aldehydes gave 8a,8b,and 9a,9b,respectively.

关键词： Synthesis and comparative study of reactivities of lactone,estor group and oxazinone ring in coumarin derivatives towards carbon or nitrogen nucleophiles ring

Fabrication of an electrochemical sensor for determination of doxorubicin in human plasma and its interaction with DNA

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Journal of Pharmaceutical Analysis 2017年第1期7卷 27-33页

作者： Reza Hajian zahra Tayebi Nafiseh shams Young Researchers and elite Club Gachsaran Branch Islamic Azad University 75818-63876 Gachsaran Iran department of chemistry College of Science Gachsaran Branch Islamic Azad University 75818-63876 Gachsaran Iran Institute of Advanced Technology Universiti Putra Malaysia 43400 Serdang Selangor Malaysia

In this work, an electrochemical sensor was fabricated for determination of an anthracycline, doxorubicin(DOX) as a chemotherapy drug in plasma based on multi-walled carbon nanotubes modified platinum electrode(Pt/MWCNTs). DOX was effectively accumulated on the surface of modified electrode and generated a pair of redox peaks at around 0.522 and 0.647 V(vs. Ag/Ag Cl) in Britton Robinson(B-R) buffer(p H 4.0, 0.1 M). The electrochemical parameters including p H, type of buffer, accumulation time, amount of modifier and scan rate were optimized. Under the optimized conditions, there was a linear correlation between cathodic peak current and concentration of DOX in the range of 0.05–4.0 μg/m L with the detection limit of 0.002 μg/m L. The number of electron transfers(n) and electron transfer-coefficient(α) were estimated as 2.0 and 0.25, respectively. The constructed sensor displayed excellent precision, sensitivity, repeatability and selectivity in the determination of DOX in plasma. Moreover, cyclic voltammetry studies of DOX in the presence of DNA showed an intercalation mechanism with binding constant(K_b) of 1.12×10~5L/mol.

关键词： Doxorubicin MWCNTs electrochemical sensor Human plasma Doxorubicin-DNA interaction

Theoretical Study of Kinetics and Thermodynamics of Hetero Diels-Alder Reaction of Thiazole and Isothiazol with Thiophene-2,5-dione

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Chinese Journal of Structural chemistry 2011年第10期30卷 1375-1380页

作者： Saeed Reza Emamian Jamileh Nabavi Fatemeh shams Ehsan zahedi chemistry department Shahrood BranchIslamic Azad University

DFT methods have been used to study the hetero Diels-Alder reaction of thiazole and isothiazole with thiophen-2,*** thermodynamic and kinetic parameters were *** relative stabilities of the transition structures corresponding to the endo/exo stereoisomers have been rationalized on the basis of the secondary molecular orbital *** analysis was carried out to calculate the synchronicity *** was shown that all reactions are synchronous.A HOMO-LUMO energy gap shows both reactions are normal electron demand.

关键词： Diels-Alder DFT kinetics thiazole isothiazole HOMO-LUMO gap

In-situ copolymerization of aniline with alkyl amine by APS:Kinetics and application

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Chinese Chemical Letters 2008年第11期19卷 1358-1362页

作者： M.Rashid shams Qamar Usmani Suhail Sabir Polymer Research Laboratory Department of ChemistryAligarh Muslim UniversityAligarh 202002India

The kinetic study of in-situ eopolymerization of aniline with o- and p-methylaniline by ammonium persulfate （APS） has been carried out. UV-vis spectroscopic method was used to investigate the course of copolymerization. Structural characterization was studied by PT-IR spectral analysis. The electronic spectra of the copolymers poly（aniline-co-p-toluidine） and poly（aniline-co-o- toluidine） show blue shift. The shift has been observed in the bands corresponding to π→π^＊ transition as well as in the exciton transition. The increase in absorbance recorded during the reaction for different concentration of aniline, o- and p-toluidine at various intervals of time of polymerization reaction indicates a growth in the polymer formation. The resulting first-order rate constant was used to calculate the rate of copolymer formation using the rate equation -d[A]/dt = kc^n.

关键词： Copolymerization Corrosion inhibition electronic and vibrational spectra

Synthesis and Crystal Structure of 2-(4-Oxo-3-o- tolyl-3,4-dihydroquinazolin-2-ylthio)acetohydrazide

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Chinese Journal of Structural chemistry 2012年第9期31卷 1329-1333页

作者： Aamer Saeed shams-ul-Mahmood Ulrich Flörke department of chemistry Quaid-I-Azam UniversityIslamabad 45320Pakistan department Chemie Fakultät fur NaturwissenschaftenUniversität PaderbornWarburgerstrasse 100D-33098 PaderbornGermany

The title compound was synthesized from 3-（2-methylphenyl）-2-thioxo-2,3-dihy- droquinazolin-4（1H）-one （4） which was prepared from 2-methylaniline in two steps. The structure was supported by the spectroscopic data and unambiguously confirmed by single-crystal X-ray diffraction studies. It crystallizes in the orthorhombic space group Pbca with unit cell dimensions a = 6.687（4）, b = 24.788（16）, c = 30.453（19）  V = 5048（5） 3 and z = 8.

关键词： quinazolinone acetohydrazide synthesis