eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
1
11
10.21608/absb.2008.8335
8335
Original Article
REACTIONS OF DIPYRIDYLKETONE WITH GROUP 8 METAL CARBONYLS IN DIFFERENT MEDIA
M. KHALIL
khalil62@yahoo.com
1
Chemistry Department, Faculty of Science, Ain Shams University, Abbassia, Cairo Egypt
Reaction of di-(2-pyridyl)ketone (dpk) with [M3(CO)12], M =Ru or Os in dioxan under reduced pressure gave the tricarbonyl derivative [Ru(CO)3(dpk)] (1) and [Os(CO)3(dpk)] (2). When these reactions were carried out in benzene/ethanol 1:1 (v:v) under reflux and reduced pressure gave the binuclear ruthenium complex [Ru2(CO)4(m-CO)(h3-dpkO,Oeth)2] (3),where h3-dpkO,Oeth is N,O,N-ethoxybis(2-pyridyl)-methanolato and the mononuclear [Os(CO)3(h3-dpkO,Oeth) (4). All complexes were characterized by elemental analysis, infrared, mass and 1H NMR spectroscopy. The spectroscopic measurements indicated that in dioxane as solvent the dpk act as bidentate ligand while in benzene/ethanol solution the dpk act as tridentate ligand. The magnetic measurements revealed that the complexes (3) and (4) are paramagnetic with change in the formal oxidation state of the ruthenium and osmium atoms from zero to +1 via oxidative addition of the OH group to ruthenium or osmium with a proton displacement to give a low-spin d7 electronic configuration The UV–Vis studies of the complexes showed blue shift compared to the ligand confirming complex formation.
https://absb.journals.ekb.eg/article_8335_e50bb86750301d9b59d397d150ec90d6.pdf
DIPYRIDYLKETONE
GROUP 8 METAL CARBONYLS
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
13
26
10.21608/absb.2008.8336
8336
Original Article
OFF-LINE SOLID PHASE SELECTIVE SEPARATION AND PRECONCENTRATION OF Cu, Zn, Pb AND Cd IN DRINKING WATER BY SOLID-PHASE EXTRACTION USING 4´-(2-HYDROXYPHENYLAZO)-3´-METHYL-1´-PHENYL-2´-PYRAZOLIN-5´-ONE FUNCTIONALIZED AMBERLITE XAD-2
N. BURHAM
1
S. ABDEL AZEEM
2
M. EL-SHAHAT
3
Chemistry department, Faculty of Science, Fayoum University, Fayoum City, Egypt
Chemistry department, Faculty of Science, Fayoum University, Fayoum City, Egypt
Chemistry Deparatment, Faculty of Science, Ain Shams University, Cairo, Egypt
A new solid – phase extraction sorbent is developed based on stepwise anchoring of two ligand molecules for the determination of copper, zinc, lead and cadmium in drinking water by flame AAS. Amberlite XAD-2 functionalized with 4´-(2-hydroxyphenylazo)-3´-methyl-1´-phenyl-2´-pyrazolin-5´-one (HPAPyr) was utilized for preconcentration/separation of these elements. The sorbent was prepared by two successive azo coupling reactions. Firstly, 2-aminophenol was anchored to the amino groups in the resin resulted from nitration followed by reduction. Then, the resulted 2-aminophenol functionalized resin was further diazotized and coupled to pyrazolone compound and the final product HPAPyr-XAD-2 was characterized by IR and elemental analysis. The optimum pH range for sorption, shaking time, exchange capacity, sample flow rate, preconcentration factor and interference from co-existing ions are investigated. All metal ions are quantitatively desorbed from the resin by 4.5 mol l-1 nitric acid solution. The sorbent provides limit of detection within the range 0.9 – 3.3 µg l-1 and concentration factor up to 250. The procedure is validated by analysis of certified material NIST-SRM 1577b. Application to drinking water showed satisfactory results with relative standard deviation RSD ≤ 8.5 %.
https://absb.journals.ekb.eg/article_8336_78d17c3672222e415d2e9866e5b2e449.pdf
4´-(2-hydroxyphenylazo)-3´-methyl-1´-phenyl-2´-pyrazolin-5´-one
Amberlite XAD-2
Preconcentration
Drinking water
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
27
39
10.21608/absb.2008.8337
8337
Original Article
ELECTROCHEMICAL BEHAVIOR OF MOLYBDENUM ELECTRODE IN ACETIC, FORMIC AND OXALIC ACID SOLUTIONS.
E. ATTIA
1
A. EL- SHENNAWY
2
W. HUSSEIN
3
Chemistry Department, Faculty of Science (for Girls), AL- Azhar University, Nasr City, Cairo, Egypt
Chemistry Department, Faculty of Science (for Girls), AL- Azhar University, Nasr City, Cairo, Egypt
Chemistry Department, Faculty of Science (for Girls), AL- Azhar University, Nasr City, Cairo, Egypt
The electrochemical behavior of molybdenum electrode in acetic, formic and oxalic acid solutions is studied. The effect of immersion time, composition medium, applied voltage, applied current density and scanning rate is investigated using potentiodynamic, potentiostatic and galvanostatic polarization measurements.
The stability of the oxide film formed on Mo electrode is affected by both the formation medium and the applied potential. In 0.5N oxalic acid, the critical applied voltage below which the current start to oscillate is equal to -80 mV. The rate of dissolution of anodic oxide film formed on Mo in oxalic acid is very rapid compared with that formed in acetic and formic acids. Also in oxalic acid solutions Mo is notably affected by applied current density in which reciprocal capacitance, Cs-1, decrease with increasing applied current density. On the contrary in acetic and formic acids Mo did not affect. In acetic acid solution, the time of anodization has little or no effect on the dissolution process.
https://absb.journals.ekb.eg/article_8337_c9cef13eb9d395d04d6eb82fecf31175.pdf
electrochemical
MOLYBDENUM ELECTRODE
acetic acid
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
41
48
10.21608/absb.2008.8995
8995
Original Article
IONIZATION OF PERLNDOPRIL PERMADIOL AND AMINEPTINE – HCL AS PHARMACEUTICAL LIGANDS AND THEIR COMPLEXES WITH DIVALENT CATIONS AND LANTHANONS.
ADEL ORABI
1
N. EL-ASSY
2
ABD EL-GWAD RADI
3
N. ABDEL-GHANY
4
SAWSSAN ABU EL-HASSAN
5
Department of Chemistry, Faculty of Science, Suez Canal University, Ismailia, Egypt
Department of Chemistry, Faculty of Education, Suez Canal University, El-Arish, Egypt.
Department of Chemistry, Faculty of Science, (Demiatta), Mansoura University, Egypt.
Department of Chemistry, Faculty of Education, Suez Canal University, El-Arish, Egypt.
Department of Chemistry, Faculty of Education, Suez Canal University, El-Arish, Egypt.
Proton – constants of Per (I) and Amin (II) ligands and the formation constants of their complexes with some transition metal ions (Zn(II) and Cu(II)) and some trivalent lanthanides (Ce(III), Pr(III), and Er(III)) ions have been determined potentiometrically in aqueous methanol medium. The effect of temperature was studied at 20, 30, and 40ºC. The thermodynamic parameters (∆Hº, ∆Gº, ∆Sº) were evaluated and discussed. The formation curves for the metal complexes were obtained and the formation constants were determined.
https://absb.journals.ekb.eg/article_8995_431857072a2a0ff9f4d411404b9ff013.pdf
potentiometry, complexes
Thermodynamic
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
67
90
10.21608/absb.2008.8996
8996
Original Article
SYNTHESIS AND REACTIONS OF SOME PYRIDINE AND THIENO [2,3-b] PYRIDINE DERIVATIVES WITH EXPECTED BIOLOGICAL ACTIVITY
A. HASSAN
1
F. FAYZ
2
Chemistry Department, Faculty of Science (Girl's), Al-Azhar University, Nasr City, Cairo, Egypt
Chemistry Department, Girl's College of Education, Saudi Arabia, Riyadh
A synthesis of pyridine-2(1H)-thione derivative 2 and thieno-[2,3-b] -pyridine derivatives 4,5 utilizing cyanothioacetamide and arylhydrazone of benzoylacetone 1 as starting compounds is described. Pyridinethione derivative 6 reacted with aromatic aldehyde to give styrylpyridinethione derivative 7. Compound 7 was reacted with chloroacetone to obtain thienopyridine derivative 8. Cycloaddition reaction was carried out on 8 with dienophiles, to afford the corresponding cycloadduct 9.Pyridinethione derivative 6 reacted with halogen-containing materials to give the corresponding thienopyridine derivatives 10, 17. the reaction of 10 with triethyl orthoformate or formic acid led to the formation of pyridothienopyrimdine derivative 11. The hydrazino derivative 13, gave with triethyl orthoformate triazolo-pyrimidothienopyridine derivative 14. Compound 10 reacted with nitrous acid to gave pyridothienotrizinone derivative 15. Thienopyridine derivative 17 reacted with triethyl orthoformate to give 18. Triazipinopyrimidothienopyridine derivative 20 obtained from compound 18 after reaction with hydrazine hydrate and acetylacetone. Compound 17 reacted with carbon disulfide to give pyrimidinedithione derivative 21.
https://absb.journals.ekb.eg/article_8996_8a493bdfe43f115443b785d18f92d762.pdf
Pyridine
THIENO [2,3-b] PYRIDINE
Biological Activity
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
91
100
10.21608/absb.2008.8997
8997
Original Article
SYNTHESIS OF NEW MICROCAPSULES FROM AGAROSE GEL AND THEIR MEDICAL APPLICATIONS
ASHRAF SEIDA
1
EZZ EL-GAMAL
2
MAHMOUD GABR
3
HASSAN IBRAHIM
4
MOHAMED EL-GHARIB
5
Chemistry department, Faculty of Science, Suez Canal University, Ismailia, Egypt.
Chemistry department, Faculty of Science, Suez Canal University, Ismailia, Egypt.
Chemistry department, Faculty of Science, Suez Canal University, Ismailia, Egypt.
Chemistry department, Faculty of Education, Suez Canal University, Port Said, Egypt.
Urology and Nephrology, Mansoura University, Mansoura, Egypt.
Prevention of rejection is critical to achieve successful pancreatic islet transplantation protection of islet cells from rejection by isolating the islets in artificial membranes has been used instead of immunosuppression treatment. In these study we investigated the microencapsulation of microencapsulated hamster islets in hydrophilic microencapsules made of agarose. The microencapsulated hamster islets were placed interaperitoneally in mice in which diabetes was induced by a single dose (150 mg/kgof body weight) of streptozotocin. Five groups were studied. The first group (5 mice) received free hamster islets (1000 islets).The second group (5 mice) received 1000 empty agarose microcapsules and 1000 free hamster islets. The third group (10 mice) received hamster islets microencapsulated in agarose (500 microcapsules). The forth group (10 mice) received 1000islet microcapsules. The fifth group (10 mice) received 1000 islet microcapsules cultured in CMRL-1066 medium for 4 weeks at 37°C . Mice of group 1 and group 2 failed to achieve normoglycemia. Recepient mice received miccroencapsulated islets group (3,4,5) maintained normoglycemia for a mean of 45 ± 5 days range (30 – 65 days). These cured mice had normal glucose tolerance tests, which indicates that islets in the microcapsules were functioning as if they are in an intact pancreas. Microcapsules, retrieved up to 30 days after transplantation, showed no evidence of tissue reaction. Our study indicate that agarose microcapsules can protect islet xenografts from rejection. These microcapsules may be suitable for human clinical islet xenotransplantation.
https://absb.journals.ekb.eg/article_8997_bff945ca04b0ecb959c348125b906f29.pdf
MICROCAPSULES
Agarose gel
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
101
121
10.21608/absb.2008.8998
8998
Original Article
EFFECT OF CALCINATION TEMPERATURE OF KAOLINITE CLAY ON THE PROPERTIES OF PORTLAND CEMENT PASTES CONTAINING METAKAOLIN
M. TAHER
1
A. EL-SAYED
2
O. FARGHALY
3
M. SHATAT
4
Chemistry Department. Faculty of Science, Al-Azhar University, Assiut, Egypt
Chemistry Department. Faculty of Science, Al-Azhar University, Assiut, Egypt
Chemistry Department. Faculty of Science, Al-Azhar University, Assiut, Egypt
Chemistry Department. Faculty of Science, Al-Azhar University, Assiut, Egypt
Metakaolin (MK) is a highly reactive pozzolan produced by calcination of kaolinite clay at high temperatures. It has a high specific surface, which makes it very suitable as a cementing material in concrete. The utilization of area calcined clay, in the form of MK, as a pozzolanic material for mortar and concrete has received a considerable attention in recent years. This interest is part of the widely spread attention directed towards the utilization of wastes and industrial by-products in order to minimize Portland cement (PC) consumption, the manufacture of which being environmentally damaging. Another reason is that mortar and concrete, which contain pozzolanic materials, exhibit considerable enhancement in durability properties. In this investigation, the physico-chemical properties of artificial pozzolanic cement pastes containing MK produced by calcination of kaolinite clay at different temperatures (700, 800, 900, and 1000oC) were studied. PC was partially substituted for by 0, 5, 10, 15 and 20 % of MK by weight at different calcination temperatures. The characteristics of prepared mortars were investigated after curing in water for different periods (3, 7, 28 and 90 days) by determination of compressive strength and total porosity. The hydration kinetics was evaluated by determination of free lime contents. IR spectroscopic analysis was used to investigate the change in structure of mortars after curing. The change in morphology and microstructure of some hardened pastes were investigated by scanning electron microscopy (SEM).
https://absb.journals.ekb.eg/article_8998_fb23ce04b58840e753a97df476f7015a.pdf
Metakaolin
Pozzolan
kaolin
Blended cement
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
123
133
10.21608/absb.2008.8999
8999
Original Article
EXPERIENCE IN ANALYZING VIBRATIONAL SPECTRA OF SOLIDS AND SOLID-SOLID INTERACTIONS
M. AFIFI
sirag@tedata.net.eg
1
Chemistry Department, Faculty of Science, Al Azhar University, Cairo, Egypt
The theoretical analysis of vibrational spectra of solid and solid-solid interactions is critically reviewed and analyzed.
https://absb.journals.ekb.eg/article_8999_c24a8f2c8e825ab8fc4a18dd33d47268.pdf
Zeolites
solid-solid interactions
vibrational spectra
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-18
19
Issue 1-A
135
151
10.21608/absb.2008.10495
10495
Original Article
EFFECT OF TWO TRIAZOLE THIONE DERIVATIVES ON CORROSION BEHAVIOR OF MOLYBDENUM IN 0.01M HCL
E. ATTIA
1
Chemistry Department, Faculty of Science (for Girls), AL- Azhar University, Cairo, Egypt.
4N- (2- hydroxy -3- triethyl ammonio- propyl-) fatty- 1, 2, 4 triazole -3- thione (12AB) and 2,4N- (bis- 2- hydroxy -3- triethyl ammonio- propyl-) fatty- 1, 2, 4 triazole -3- thione (12ABB) were synthesized, characterized and tested as surfactant corrosion inhibitors for Mo in 0.01 M HCl solution using galvanostatic, potentiodynamic and potentiostatic polarization techniques. Concentrations of the inhibitors were ranged from 1x10−6 to 1 (wt. %). The obtained results using galvanostatic polarization on bare metal showed that thickness of adsorbed layer decreased with increasing concentration of 12AB while adverse trend was observed with 12ABB. On the other hand the anodic oxide film formed at 100mAcm-2 up to 0.268V (SCE) was susceptible to a dissolution process with the presence of two corrosion rates for each concentration of the two additives. Potentiodynamic polarization illustrated that increase of additive concentration lowered corrosion current densities affecting anodic reaction more than cathodic one. The protection efficiency increased with increasing inhibitor concentration. The low values of IE. % indicated the presence of electrostatic attraction between inhibiting molecules and the electrically charged surface of metal. Adsorption followed the kinetic thermodynamic model, Langmuir and Flory–Huggins adsorption isotherms. 12ABB showed better inhibiting action than that of 12AB due to the presence of two side chains in its structure. Potentiostatic polarizations indicated that when the concentration of the additives 12AB and 12ABB exceeded a critical value, ≥0.1Wt.%, no inhibition effect.
https://absb.journals.ekb.eg/article_10495_50729c0d381c830b60e29b181dab02dd.pdf
triazole thione
Corrosion
molybdenum
galvanostatic
Potentiodynamic
potentiostatic
Polarization
Adsorption
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
153
167
10.21608/absb.2008.9000
9000
Original Article
ELECTROCHEMICAL BEHAVIOR OF STEEL ALLOYS AS AFFECTED BY PHOSPHORIC ACID
A. AHMED
1
R. ABOU SHAHBA
2
IBRAHIME GHAYAD
3
E. ATTIA
4
W. HUSSEIN
5
Chemistry Department, Faculty of Science (for Girls), AL-Azhar University, Nasr City, Cairo, Egypt
Chemistry Department, Faculty of Science (for Girls), AL-Azhar University, Nasr City, Cairo, Egypt
Central metallurgical research and development institute.
Chemistry Department, Faculty of Science (for Girls), AL-Azhar University, Nasr City, Cairo, Egypt
Chemistry Department, Faculty of Science (for Girls), AL-Azhar University, Nasr City, Cairo, Egypt
The behavior of two steel alloys in phosphoric acid solutions alone and with addition of organic and inorganic compounds was studied using open circuit potential and potentiodynamic polarization techniques. Open circuit potential measurements of the two stainless steel electrodes in different concentrations of H3PO4 showed that the rates of film thickening of the two electrodes are independent of the solution concentration. Potentiodynamic polarizations illustrate that, upon increasing Na3PO4 concentration in 0.5M H3PO4 the pH of the solutions changed in the range from 1.7 to 10.7 and the corrosion rate decreases. Electrode type (II) has inhibition efficiency more than electrode type (I). AT compound (3 amino 1, 2, 4-triazole) has proven to be efficient inhibitor for pitting corrosion of stainless steel in phosphoric acid solutions. The inhibition efficiency was increased by increasing the inhibitor concentration. The inhibitive property may be argued to the formation of a compact Fe-AT complex film on the electrode surface.
https://absb.journals.ekb.eg/article_9000_66bc536b78b295011304a08c6b65b7f5.pdf
electrochemical
STEEL ALLOYS
phosphoric acid
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
169
178
10.21608/absb.2008.9001
9001
Original Article
THE CHARACTERIZATION MOTOR FUELS IN YEMEN AND COMPARE THEM WITH INTERNATIONAL FUELS SPECIFICATIONS.
ABDO SALEH AL SUBARI
sabbari67@yahoo.com
1
Thamar University, Faculty of Applied Science, Department of chemistry, Yemen
The main purpose of this search is to characterize our local Motor Fuels and compare them with international fuels aiming to contribute in finding a solution to improve their quality.
Fuels affected by legislation include gasoline, diesel and heavy fuel oil, this trend is now spreading to other regions of the world, wherever similar clean fuels regulations are being planned and implemented.
The paper deals with the current specifications for local market and ways to meet international requirements. Analysis for the produced Motor gasoline and diesel fuel in Yemen Refining Companies were done and proposed changes for the qualities and technological processes are suggested
https://absb.journals.ekb.eg/article_9001_41b7a9d57ba0f551eea90752bb74172b.pdf
MOTOR FUELS
Yemen
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
179
194
10.21608/absb.2008.9002
9002
Original Article
THE RELATION BETWEEN THE MICROSTRUCTURE OF CARBON STEEL (0.24 C% & 0.38 C%) AND CORROSION PROTECTION
S. SELIM
1
A. MOHAMED
2
G. Al-Hazmi
3
A. Ali
4
Chemistry Department, Faculty of Science, Al-Azhar University, Cairo, EGYPT
Chemistry Department, Faculty of Science, Al-Azhar University, Cairo, EGYPT.
Chemistry Department, Faculty of Science, Taiz University, Taiz, YEMEN
Chemistry Department, Faculty of Science, Taiz University, Taiz, YEMEN
The effect of carbon percent on the corrosion of steel in ethanol – aqueous H2SO4 solution has been studied by using weight loss technique. The effect of presence of foreign atoms in steel composition on the corrosion resistance has been investigated. Beside that, the effect of heat treatment on the corrosion rates has been interpreted. The inhibitive action of N, N-dihydroxy ethyl acryl-amide on the corrosion rate of steel appears high efficiency for all samples in all cases under study. The corrosion behavior is interpreted in view of the microstructure of samples before and after heat treatment. There are two wet corrosion processes that affected by carbon percent in the localized area. Before heat treatment the corrosion rate is more dependent upon inter-granular corrosion type while, increasing C % or by quenching regime the corrosion rate is more dependent upon allotropic–galvanic corrosion type. The corrosion rate in absence of inhibitors classified as cathodic control while it classified as cathodic–anodic control in presence of inhibitor.
https://absb.journals.ekb.eg/article_9002_d5522de402838600ed6d8e3dc7b0b014.pdf
steel microstructure
corrosion of low and medium carbon steel
N, N-dihydroxy ethyl acryl-amide
Heat treatment
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
195
204
10.21608/absb.2008.9912
9912
Original Article
ARIOUS MODIFIED POLYESTERAMIDE VARNISHES AS ANTIMICROBIAL SURFACE COATING VEHICLES.
H. ABD EL-WAHAB
1
Department of Chemistry, Faculty of Science (boys), Al-Aazhr University, Cairo, Egypt.
New modified polyesteramide compositions were prepared and evaluated as vehicles for surface coating Resin was prepared by partial replacement of hydroxyl ethyl fatty acid amide (HEFAA) using 6,8-Dibromocumarin-3-N-bis(2-hydroxyethyl) carboxamide which carried out by solvent technique, This modification, as expected, improved the film performance and durability and lead to substantial antimicrobial growth control.
https://absb.journals.ekb.eg/article_9912_86b67f95bd8e0cef5022a01621d0bd9a.pdf
Polyester amide
Surface coating
Biological Activity
Antimicrobial varnishes
Protective coating
Biocide activity of organic coating
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
205
222
10.21608/absb.2008.9913
9913
Original Article
SYNTHESIS AND CHARACTERISATION OF BISPHENOL A NOVOLAC EPOXY RESINS FOR COATING APPLICATIONS
N. SHAKER
1
Egyptian Petroleum Research Institute, Nasr City 11727, Cairo, Egypt
Bisphenol A novolacs were synthesized in a melting process using para formaldehyde, and in a solution process using formalin solution and oxalic acid catalyst. 1H-NMR investigations show a higher content of methylene bridges in the novolacs synthesized by the melting process. These novolacs were analyzed by GPC and FT-IR spectroscopy. The bisphenol A novolac was cured with 1,2-amino ethyl piperazine (AEP ) as a curing agent for epoxy resins. The networks synthesized were evaluated as organic coatings for steel. The mechanical properties of the cured epoxy resins were tested and the chemical resistances of the cured resins were evaluated through salt spray resistance, hot water, solvents, acid and alkali resistance measurements. The data indicate that the cured epoxy resins have excellent chemical resistance as organic coatings among other resins.
https://absb.journals.ekb.eg/article_9913_520004d72a29330528588f58dd8750e7.pdf
Bisphenol
NOVOLAC EPOXY RESINS
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
223
232
10.21608/absb.2008.9915
9915
Original Article
SYNTHESIS, SURFACE AND ANTIMICROBIAL PROPERTIES OF FATTY MORPHOLIDE AND PIPERIDIDE DERIVATIVES
B. EL-SADEK
1
F. ABDEL SALAM
2
E. KANDEEL
3
S. BAKR
4
Chemistry Department, Faculty of Science (Girls), Al-Azhar University, Nasr City, Egypt
Chemistry Department, Faculty of Science (Girls), Al-Azhar University, Nasr City, Egypt
Chemistry Department, Faculty of Science (Girls), Al-Azhar University, Nasr City, Egypt
Chemistry Department, Faculty of Science (Girls), Al-Azhar University, Nasr City, Egypt
Unsaturated fatty N-acyl morpholide and piperidide derivatives were prepared by the reaction of the acid chloride of oleic and linoleic acids as well as the mixed fatty acid chlorides of olive, linseed and castor oils with morpholine and piperidine. The sodium bisulfite and mercapto acetic acid were added to the prepared unsaturated fatty amides to give sulfonated and methylthiocarboxylate morpholide and piperidide derivatives.
These derivatives were characterized using infrared (IR), 1H nuclear magnetic resonance (NMR) and mass spectroscopy (MS), they showed excellent lowering power of surface tension, foaming stability and emulsifying property. On the other hand, these derivatives showed a broad antimicrobial spectra as high as chloramphenicol against all the tested microorganisms. It was found that compounds containing a carboxylate hydrophilic group were less efficient than those with a suflonate group with respect to foaming power, foam stability, emulsification and antimicrobial effect.
https://absb.journals.ekb.eg/article_9915_f1c158f8151e00b2af4289fe3a351766.pdf
FATTY MORPHOLIDE
PIPERIDIDE DERIVATIVES
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
233
244
10.21608/absb.2008.10044
10044
Original Article
PHENOL/FORMALDEHYDE-BASED SOYBEAN EPOXY ESTERS FOR SURFACE COATINGS
N. SHAKER
1
Egyptian Petroleum Research Institute, Nasr City, Cairo, Egypt
High performance Phenol/formaldehyde-based soybean epoxy esters were prepared by reacting soybean oil fatty acids with epoxy resins which were prepared by the epoxidation of phenol /formaldehyde resins (1:1, 3:2, 2:1) using epichlorohydrin. The epoxy esters were blended with alkyd resin and the film characteristics of these blends were studied at different pigmentation level. It was found that the performance of the cured films is excellent with regard to resistance to water and solvents (acetone, ethanol, methanol, ethyl methyl ketone, toluene), while the resistance to alkali poor and increasing the ratio of phenol /formaldehyde increase the resistance to acids. All the coating films exhibited a very good adhesion to metallic substrates, good impact, scratch hardness, flexibility and storage stability. They also provide several benefits for the manufacture of epoxy coating that include low price, versatility, minimal volatile organic content (VOC), and minimal environmental impact.
https://absb.journals.ekb.eg/article_10044_d41d8cd98f00b204e9800998ecf8427e.pdf
Phenol
formaldehyde resins
soybean epoxy esters
chemical resistance
mechanical resistance
storage stability
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
245
267
10.21608/absb.2008.10089
10089
Original Article
FRACTIONAL FACTORIAL DESIGN APPROACH FOR STUDYING IN VITRO TRANSDERMAL DELIVERY OF GRANISETRON USING ELECTROPORATION
SAMIA NOUR
1
MOHAMED ELEWA
2
Randa Abd El-rehim
randa_tag@yahoo.co.uk
3
Department of Pharmaceutics, Faculty of Pharmacy, Cairo University, Cairo, Egypt.
Department of Electrical Engineering, Faculty of Engineering, Benha University , Egypt.
Department of Pharmaceutics, Faculty of Pharmacy, Cairo University, Cairo, Egypt.
Granisetron Hydrochloride is a 5-hydroxytryptamine 3 (5-HT3) receptor antagonist used for the prevention and treatment of nausea and vomiting associated with cancer chemotherapy. Based on the hydrophilicity of this drug (pka=9.4) it is unlikely that passive diffusion across the skin could deliver therapeutic amounts from a large sized patch. This study was conducted to evaluate the feasibility of in vitro transdermal delivery of granisetron using electroporation across full thickness hairless rat skin. A 24-1fractional factorial design was used to determine the most important variables affecting the transdermal delivery of granisetron using electroporation. The variables studied and respective levels investigated were drug concentration (10, 20 mg/ml), voltage (155, 310 volt), pulse duration (12, 24 ms) and number of pulses (100, 200 pulses). Permeation profiles were used for the representation of data, where Q: the cumulative amount permeated per cm2 (µg/cm2) was plotted against time (min). The selected dependent variable (response) was Q120 which is the cumulative amount permeated per cm2 after 2 hours. Design-expert version 7.0.0 was used for the statistical evaluation. The results of the analysis of variance (ANOVA) revealed that Q120 was significantly affected by the voltage, pulse duration and number of pulses. The drug concentration had a non significant effect on Q120. A reduced polynomial regression equation which expresses the influence of process parameters on the response was obtained to enable navigation of the experimental space.
https://absb.journals.ekb.eg/article_10089_65b1e228e522c0513245b0352fd0a333.pdf
Granisetron
Transdermal
electroporation
Fractional factorial design
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
269
281
10.21608/absb.2008.10493
10493
Original Article
OPEN-CIRCUIT AND POTENTIODYNAMIC STUDY ON THE ELECTROCHEMICAL BEHAVIOR OF TIN ELECTRODE IN SULPHURIC ACID AND SODIUM HYDROXIDE SOLUTIONS
R. ABOU SHAHBA
1
A. AHMED
2
E. ATTIA
3
A. EL-SHENNAWY
4
Chemistry Department, Faculty of Science (for Girls), AL- Azhar University, Cairo, Egypt.
Chemistry Department, Faculty of Science (for Girls), AL- Azhar University, Cairo, Egypt.
Chemistry Department, Faculty of Science (for Girls), AL- Azhar University, Cairo, Egypt.
Chemistry Department, Faculty of Science (for Girls), AL- Azhar University, Cairo, Egypt.
The electrochemical behavior of tin electrode in H2SO4 and NaOH solutions is studied in details using open- circuit potential measurements and potentiodynamic polarization techniques. The identification of the elements present in the surface of specimen after immersion in the two test solutions is performed using an energy dispersive X-ray analysis(EDX).
Open- circuit potential measurements show that for tin electrode in low concentrations of H2SO4 and NaOH solutions the passivity was increased with dilution. At higher concentrations, dissolution of the pre-immersion oxide film occurs in which the corrosivety of NaOH is higher than that of H2SO4 solutions. Passivation of tin in NaOH solutions appears to take place in two steps. The first involves formation of SnO or Sn(OH)2, in the second step oxidation to Sn(OH)4 takes place.
Potentiodynamic polarization techniques illustrate that the dissolution of tin in sulphuric acid occurs through the participation of both OH¯ and SO42- ions through an intermediate of (SnHSO4OH) species. The potentiodynamic curves for tin in sodium hydroxide solutions exhibits an active/passive transition. The active dissolution region involves two anodic peaks prior to permanent passivity. The first anodic peak is due to the formation of Sn(OH)2 whilethe second peak corresponded to the formation of Sn(OH)4 in addition to the formation of the soluble stannate ions. Dehydration of unstable Sn(OH)4 to the stable SnO2 can occur on the tin electrode during the potential sweep to positive direction. Increasing concentrations of H2SO4 and NaOH solutions led to enhance the corrosion current (icorr.), and corrosion potentials (Ecorr)shift towards more negative values. EDX analysis showed that Sn % present on the surface of tin electrode in 1M of each of NaOH and H2SO4 solutionswas 91.82 and 83.52 respectively.
https://absb.journals.ekb.eg/article_10493_df79dd52c37ed5cc731a0e372301571e.pdf
OPEN-CIRCUIT
Potentiodynamic
electrochemical
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
283
294
10.21608/absb.2008.10102
10102
Original Article
CORROSION OF CARBON-STEEL ALLOY IN 0.1M NITRIC ACID IN PRESENCE OF PLASTIC WASTE AS CORROSION INHIBITORS
REDA ABDEL HAMEED
mredars2@yahoo.com
1
H. ISMAIL
2
Chemistry Department, Faculty of Science, Al-Azhar University, Cairo, Egypt.
Egyptian Petroleum Research Institute, Nasr City 11727, Cairo, Egypt.
Recyclization of poly (ethyleneterphthalate), (PET), with Diethanolamine and Triethanolamine having 1:2 wt% of PET: wt% of DEA or wt% TEA, in presence of manganese acetate as a catalyst. The inhibition action of the prepared compounds (D2 & T2) on the corrosion of carbon-steel which used in the manufacture of petroleum pipelines in nitric acid was evaluated, at different concentrations of inhibitors from (50-250 ppm) at different temperatures, ranged from (303-333 K). The polarization curves indicate that these compounds may act as mixed-type inhibitors. The adsorption of the prepared compounds on C-steel was found to follow the Langmuir adsorption isotherm,they also obey El-Awady isotherm. The values of activation energies (Ea*) and all thermodynamic activation parameters which determined, indicating that the type of adsorption was chemical adsorption.
https://absb.journals.ekb.eg/article_10102_62b7e306714084c284f3a11bc8dc9b9c.pdf
recycling
Nitric acid
Corrosion
Inhibitor
carbon steel
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
295
307
10.21608/absb.2008.10491
10491
Original Article
BLEACHING OF LOOM-STAT COTTON FABRIC USING ACTIVATED SODIUM CHLORITE / HEXAMETHYLENETETRAMINE SYSTEM
M. El-BISI
1
E. ABD ELHALIM
2
M. EL-RAFEI
3
National Research Center, Dokki, Cairo, Egypt.
National Research Center, Dokki, Cairo, Egypt.
National Research Center, Dokki, Cairo, Egypt.
Hexamethylenetetramine (HMTA) has been investigated as novel activator for sodium chlorite to effectively bleach loom state cotton fabric in one step process and in slightly alkaline medium. This was done with a view to avoiding the troubles associated with evaluation of chlorine dioxide during chlorite bleaching. Two techniques have been separately investigated to carry out the bleaching process, namely, exhaustion and pad steam technique. The process parameters in each technique have been investigated. Results obtained show that the addition of HMT A decreased the decomposition percent of sodium chlorite during the bleaching process. It has been also found that loom state cotton fabric can be bleached in one step process with NaClO2 /HMT A using either exhaustion or pad-steam technique. In exhaustion system maximum W.I and wettability of bleached cotton fabric was obtained when loom state cotton fabric was bleached with an aqueous solution containing 3 g/l NaClO2 and 0.08 g/l HMT A. Whereas, in pad steam technique, maximum W.I and wettability of bleached cotton fabric was obtained when loom state cotton fabric was bleached with an aqueous solution containing 20 g/l NaClO2 and 0.6 g/l HMT A then steamed for 60 min.
https://absb.journals.ekb.eg/article_10491_730a39d0cbb40789f5e21c473e20e3fd.pdf
bleaching
Cotton fabric
Hexamethylenetetramine
Sodium chlorite
eng
Al-Azhar University, Faculty of Science (Boys)
Al-Azhar Bulletin of Science
1110-2535
2636-3305
2008-06-01
19
Issue 1-A
309
335
10.21608/absb.2008.10043
10043
Original Article
EFFECT OF ADDITION OF SOME ORGANIC AND INORGANIC COMPOUNDS ON THE PITTING CORROSION OF STAINLESS STEEL ELECTRODES
A. AHMED
1
R. ABOU SHAHBA
2
E. ATTIA
3
IBRAHIME GHAYAD
4
W. HUSSEIN
5
Chemistry Department, Faculty of Science (for Girls), Al-Azhar University, Nasr City, Cairo, Egypt
Chemistry Department, Faculty of Science (for Girls), Al-Azhar University, Nasr City, Cairo, Egypt
Chemistry Department, Faculty of Science (for Girls), Al-Azhar University, Nasr City, Cairo, Egypt
Central metallurgical research and development institute, Cairo, Egypt.
Chemistry Department, Faculty of Science (for Girls), Al-Azhar University, Nasr City, Cairo, Egypt
The corrosion behavior of two stainless steel electrodes with different chemical compositions in different salt solutions of Cl¯ ions (NaCl, FeCl3 and HgCl2) was studied. The corrosion behavior in 3.5% NaCl with and without different concentrations of two different triazole derivatives, 3-amino-1, 2, 4 triazole (AT) and 4-amino-5-mercapto-1, 2, 4 triazole (AMT) and Na2S2O3 (50 to 200ppm.) was studied. Open circuit potential measurements, potentiodynamic cyclic anodic polarization (PCAP) and surface morphology techniques were used in this study.
Obtained results showed that NaCl is more aggressive comparing with FeCl3 and HgCl2. As the concentration of sodium chloride increased, the (PCAP) curves indicated the presence of pitting or crevice corrosion breakdown potential which sustained the increase of anodic current density. The plots of pitting potential (Epit.), or protection potential (Ep) versus log [Cl¯] at 25oC, for the two stainless steel electrodes were linearly decreased with the increase of the logarithm of chloride concentration. Also the increase of scan rate increases the localized pitting corrosion. The additions of sodium thiosulphate to 3.5% NaCl enhance pitting corrosion as compared with that found in pure sodium chloride solution. On the contrary, increasing concentration of (AT) and (AMT) in NaCl solution was found to greatly enhance IE%. The adsorptive behavior of the investigated inhibitors on the steel surface followed Langmiur-type isotherm. These results indicate the suitability of the use of the investigated inhibitors. Electrode type (I) has a greater tendency for pitting than electrode type (II) due to the percentage of nickel in electrode type (I) is half that of electrode type (II).
https://absb.journals.ekb.eg/article_10043_e2f292ae8f913f0033a08f45d600fe77.pdf
ORGANIC AND INORGANIC
PITTING CORROSION
STAINLESS STEEL ELECTRODES