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2008

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Full-Text Articles in Life Sciences

A New Species Of Gobiid Fish,Luciogobius From Ryukyus, Japan(Teleostei: Gobiidae), I-Shiung Chen, Toshiyuki Suzuki, Hiroshi Senou Dec 2008

A New Species Of Gobiid Fish,Luciogobius From Ryukyus, Japan(Teleostei: Gobiidae), I-Shiung Chen, Toshiyuki Suzuki, Hiroshi Senou

Journal of Marine Science and Technology

A new gobiid fish has been collected from Ryukyu Archipelagos of Japan. This species is described herein as a new species, Luciogobius ryukyuensis sp. nov. It is characterized by the following unique combination of features: (1) second dorsal fin rays: I/11 and anal fin rays I/11; (2) pectoral fin rays 16 and with one upper, very short free soft ray; (3) vertebral count 37; and (4) specific coloration: head and body with many rounded light creamy white spots above creamy yellow to yellowish brown background. A diagnostic key to all nominal species of Luciogobius from West Pacific are provided herein.

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Minerva 2008, The Honors College Dec 2008

Minerva 2008, The Honors College

Minerva

This issue of Minerva includes an article on the completion of the restoration of Colvin Hall; a reflection by Ruth Nadelhaft, former UMaine Honors program director; and an article on Honors alumnus and Nobel Peace Prize winner Bernard Lown and his 2008 Rezendes Visiting Scholar in Ethics Lecture/Distinguished Honors Graduate Lecture.

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"Absolutely Part Of What We Should Be Doing": Kevin Curry, Water Filters And The International Mission Of The Modern University, Andrew C. Holman Dec 2008

"Absolutely Part Of What We Should Be Doing": Kevin Curry, Water Filters And The International Mission Of The Modern University, Andrew C. Holman

Bridgewater Review

No abstract provided.

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Five Decades Of Agricultural Policies In Nigeria: What Roles Has Statistics Played?, Akinboyo O. I Dec 2008

Five Decades Of Agricultural Policies In Nigeria: What Roles Has Statistics Played?, Akinboyo O. I

Bullion

All over the country and internationally, the publications of the Central Bank of Nigeria (CBN) such as the Annual Report and Statement of Accounts, the Statistical Bulletin, Economic and Financial Review, the Bullion and Nigeria: Major Economic and Banking Indicators and those of the National Bureau of Statistics (NBS) have become a veritable source of data and reference materials on Nigeria. Without basic i n f o r m a t i o n o n e c o n o m i c developments, it would be very difficult for policy makers to assess economic performances. The f o …

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Bio Buzz Newsletter, Issue 2, December 2008, Department Of Biology Dec 2008

Bio Buzz Newsletter, Issue 2, December 2008, Department Of Biology

Biology Buzz Newsletter

Denison University Biology Department newsletter for 2008

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Yersiniae Virulence Factors: Type Iii Secretion System, Jessica Blanco Dec 2008

Yersiniae Virulence Factors: Type Iii Secretion System, Jessica Blanco

Mako: NSU Undergraduate Student Journal

Several Gram-negative pathogenic bacteria have evolved a complex protein secretion system termed the Type Three Secretion System (TTSS) to deliver bacterial effector proteins into host-cells that then modulate host-cellular functions. These bacterial devices are evolutionarily related to the flagellar apparatus. Although the TTSSs are substantially conserved among different species, the effector molecules they deliver are species-unique. There exist three human pathogenic Yersiniae. Yersinia enterocolitica and Yersinia pseudotuberculosis cause self-limiting gastro-enteric diseases and infect mesenteric lymph nodes, while Yersinia pestis is transmitted by fleas and can be aerosolized, causing the lethal disease known as plague (also known as Black Death). The …

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Streptococcus Pyogenes: A Versatile Human Pathogen, Maria E. Cevallos Dec 2008

Streptococcus Pyogenes: A Versatile Human Pathogen, Maria E. Cevallos

Mako: NSU Undergraduate Student Journal

Streptococcus pyogenes is one of the most medically relevant genera of Gram positive bacteria. S. pyogenes belongs to Group A streptococcus (GAS), the most pathogenic streptococci. S. pyogenes is exclusively a human pathogen that is known for its ability to cause a wide array of infections ranging from superficial pharyngitis and impetigo to invasive life threatening conditions including septicemia, necrotizing fasciitis, and streptococcal toxic shock syndrome. The dissemination of S. pyogenes within a human host is dependent upon virulence factors aimed at host immune system evasion leading to infection. More specifically, S. pyogenes’ virulence factors are required for bacterial …

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Remarks On The Stability Of Some Size-Structured Population Models Iii: The Case Of Constant Inflow Of Newborns, Mohammed El-Doma Dec 2008

Remarks On The Stability Of Some Size-Structured Population Models Iii: The Case Of Constant Inflow Of Newborns, Mohammed El-Doma

Applications and Applied Mathematics: An International Journal (AAM)

The stability of some size-structured population dynamics models are investigated. We determine the steady states and study their stability. We also give examples that illustrate the stability results. The results in this paper generalize previous results, for example, see Calsina, et al. (2003), El- Doma (2006) and El-Doma (2008).

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Utility Of N-2-Pyridyl–3-Oxobutanamide In Heterocyclic Synthesis: Synthesis Of New Dihydropyridine, Fused Pyridine, Pyridopyridone, Pyridazine And Pyridopyrimidinethione Derivatives, I. Abdel Hafiz, A. Khodair, Safaa Baker, A. Hussein Dec 2008

Utility Of N-2-Pyridyl–3-Oxobutanamide In Heterocyclic Synthesis: Synthesis Of New Dihydropyridine, Fused Pyridine, Pyridopyridone, Pyridazine And Pyridopyrimidinethione Derivatives, I. Abdel Hafiz, A. Khodair, Safaa Baker, A. Hussein

Al-Azhar Bulletin of Science

2-Aminopyridine was fused with ethyl acetoacetate for two hours to yield the N-2-pyridyl–3-oxobutanamide (1). However, when the reaction time was increased to 5 hours compound 3 was obtained. Condensation of 3 with benzaldehyde gave 4. The reaction of pyridopyridone 3 with arylidenemalononitrile 7a-c afforded 4H-pyran derivatives 10a-c. In contrast to the behavior of arylidenemalononitriles 7a-c towards pyridopyridine 3, benzylidenemalononitrile 7d reacted with compound 3 to give the product 11. Compound 1 was allowed to react with arylidenemalononitriles to give the dihydropyridine derivatives 17a-d. Alkylation of compound 1 with alkylating agents has been also reported. Thus, compound 1 was condensed with …

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Callus Culture Of Trigonella Foenum Graecum As A Plant Tissue Culture Alternative Of Antibacterial Activity, Esam Hussein, Abdul-Rahman Al-Dubaie, Amin Elhakimi, Aziza Taj-Eldeen Dec 2008

Callus Culture Of Trigonella Foenum Graecum As A Plant Tissue Culture Alternative Of Antibacterial Activity, Esam Hussein, Abdul-Rahman Al-Dubaie, Amin Elhakimi, Aziza Taj-Eldeen

Al-Azhar Bulletin of Science

In the present study, Fenugreek (Trigonella foenum graecum) seeds were surface sterilized and allowed to germinate on hormone free Murashige and Skoog's culture media for one week. Hypocotyls were cut into 0.5 mm length segments. Callus morphogenesis was achieved from the hypocotyls segments Using Murashige and Skoog's culture media supplemented with benzyl adenine and naphthalene acetic acid. The best callus biomass was obtained with 2 mg/l (BA) plus 1.5 mg/L (NAA) and the growth biomass was measured after 4 weeks. This concentration was then used to plot the growth curve of callus under both dark and light growth conditions. Calli …

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Physicochemical Properties Of Metakaolin-Lime Pastes At Different Calcination Temperatures Of Kaolinite Clay, M. Taher, A. El-Sayed, O. Farghaly, M. Shatat Dec 2008

Physicochemical Properties Of Metakaolin-Lime Pastes At Different Calcination Temperatures Of Kaolinite Clay, M. Taher, A. El-Sayed, O. Farghaly, M. Shatat

Al-Azhar Bulletin of Science

The study of metakaolin-lime hydration process is of great interest in the field of building materials technology.This study aimed to investigate experimentally the physicochemical properties of pastes containing metakaolin (MK) and lime as activator. MK was produced by calcining Kalabsha kaolinite clay (Aswan, Egypt) at different calcination temperatures 700,800,900 and 1000oC for 2 hr. Five mixes were prepared by partial substitution of MK by 5,10,15,20 and 25% wt CaO ( from CaCO3) by weight, then hydrated up to 90 days . The characteristics of prepared specimens were investigated by measuring compressive strength and total porosity. The hydration kinetics were evaluated …

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Impact Of Irrigation Frequencies, Potassium Fertilizer And Vitamin Treatments On Yield, Nutrients And Amino Acid Contents Of Bread Wheat Grains, Kh El-Aref, M. Faragallah, S. Desouky Dec 2008

Impact Of Irrigation Frequencies, Potassium Fertilizer And Vitamin Treatments On Yield, Nutrients And Amino Acid Contents Of Bread Wheat Grains, Kh El-Aref, M. Faragallah, S. Desouky

Al-Azhar Bulletin of Science

This study is conducted to investigate the effect of irrigation intervals in combination with soil application and / or foliar spray of potassium fertilizer and soaking in some vitamins (ascorbic acid and pyridoxine) on wheat yield, certain nutrients and amino acid contents in grains, as well as field water use efficiency. The main aim of the study is to save of the irrigation water without reduction of wheat yield with facility of practical application. Two field experiments were carried out during the two successive winter seasons of 2005/2006 and 2006/2007 at the experimental farm, Faculty of Agriculture, Al-Azhar University at …

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Utilization Of The Egyptian Bentonite Ore Based On New Modified Alkyds In Anticorrosive Coating Formulations, H. Abd El-Wahab, M. Abd El-Fattah, M. Abdou, F. Abd El-Hai Dec 2008

Utilization Of The Egyptian Bentonite Ore Based On New Modified Alkyds In Anticorrosive Coating Formulations, H. Abd El-Wahab, M. Abd El-Fattah, M. Abdou, F. Abd El-Hai

Al-Azhar Bulletin of Science

New modified alkyd resin compositions containing Egyptian bentonite ore (high grades) are evaluated as anticorrosive coating compositions for steel protection. The results indicated substantial corrosion inhibiting properties.

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Effect Of Salinity On Some Wheat (Triticum Aestivum) Cultivars, Omar Almaghrabi Dec 2008

Effect Of Salinity On Some Wheat (Triticum Aestivum) Cultivars, Omar Almaghrabi

Al-Azhar Bulletin of Science

Four wheat cultivars of Giza 9, Giza 7, Sakha 94 and Sakha 61 were cultivated under increasing NaCl levels (0.0, 50, 100, 150 and 200 mM NaCl). The tested morphological characters of shoot and roots (fresh and dry weights as well as, shoot height of the cultivars indicated that as the salinity stress increased lower values of the tested characters elucidated. The tested cultivars showed different capacities toward salt stress, and they can be arranged in the following order according to their efficiency toward salt stress: Sakha 94> Sakha 61> Giza 9 > Giza 7. Under the same conditions the cultivars …

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Synthesis Some New Quinoline Derivative Incorporated With Other Heterocyclic Compounds, Ragab El-Sayed, A. Salman Dec 2008

Synthesis Some New Quinoline Derivative Incorporated With Other Heterocyclic Compounds, Ragab El-Sayed, A. Salman

Al-Azhar Bulletin of Science

Reaction of 2-(quinolin-8-yloxy)acetohydrazide 1with phenyl isothiocyanate, carbon dsulphide, nitrous acid,active methylene compound and aromastic aldehydes afforded different heterocyclic compounds containing quinoline moiety 2-11. The structures of the new compounds confirmed by elemental analyses,spectroscopic measurements and chemical reactions.

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Effect Of Salicylic Acid On Photosynthesis And Some Antioxidant Enzymes Of Stressed Scenedesmus Obliquus Cultures, S. Desouky Dec 2008

Effect Of Salicylic Acid On Photosynthesis And Some Antioxidant Enzymes Of Stressed Scenedesmus Obliquus Cultures, S. Desouky

Al-Azhar Bulletin of Science

This study followed the effect of salicylic acid on growth criteria, photosynthetic pigments, photosynthesis, respiration, proline and the activities of some antioxidant enzymes of stressed Scenedesmus obliquus cultured for 7 days. The growth criteria (cell number and dry weight) and total pigments ofnon- stressed and stressed Scenedesmus obliquus cultures were significantly increased, when the algal cultures were subjected to 200 mM NaCl and treated with 100and 200 ppm of salicylic acid. Also, Photosynthesis (oxygen evolution), respiration (dark oxygen uptake), proline, amino acids and catalase enzyme of non- salinized and salinized Scenedesmus obliquus cultured were significantly increased, when the algal cultures …

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Encapsulation Of Nickel(Ii)-Schiff Base Complex In Y-Zeolite For In Situ Chemisorption Of Carbon Monoxide, Tarek Salama Dec 2008

Encapsulation Of Nickel(Ii)-Schiff Base Complex In Y-Zeolite For In Situ Chemisorption Of Carbon Monoxide, Tarek Salama

Al-Azhar Bulletin of Science

Encapsulation of nickel(II) complex of the Schiff base-type ligand (salicylidene-p-aminobenzoic acid) in the intracrysatalline nano-pores of zeolite-Y is reported. The zeolite-encapsulated trinuclear Ni(II)-Schiff base complex was prepared by diffusion of the ligand through pores of the zeolite, already exchanged with the respective metal (flexible ligand method). The host/guest compound obtained was characterized by elemental analysis, spectroscopic (IR and electronic) studies, surface texture, thermal analysis and powder x-ray diffraction (XRD). The solids were subjected to in situ FT-IR study of adsorbed carbon monoxide. IR and UV-vis as well as XRD data indicate that the chemical stoichiometry of the complex remains intact …

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Synthesis, Antibacterial, Anti-Inflammatory And Anti-Allergic Activities Of 2,4-Pyridinedicarbohydrazide And Its Related Derivatives, Osama Abd El-Salam, Mohamed Abdulla Dec 2008

Synthesis, Antibacterial, Anti-Inflammatory And Anti-Allergic Activities Of 2,4-Pyridinedicarbohydrazide And Its Related Derivatives, Osama Abd El-Salam, Mohamed Abdulla

Al-Azhar Bulletin of Science

2,4-Pyridinedicarbohydrazide 3 was used in synthesizing several new heterocyclic compounds with expected potential biological activity, via its reaction with various chemical reagents. A series of bis-(arylmethylidene)pyridine-2,4-dicarbohydrazides 4a-e were synthesized by condensation of 3 with various aldehydes. Further, replacement of the dicarbxylic acid functionality of 1 with five membered heterocycles, in the hope of obtaining additional pharmacological activity, encouraged us to synthesize some 2,4-bis-{pyrazolyl 5; pyrazolonyl 6; 1,3,4-oxadiazolyl 7, 9, 11, 14; 1,2,4-triazolyl 15 and triazolo[3,4-b][1,3,4]thiadiazinyl 17}pyridines.The structures of the synthesized products were identified by elemental analysis, MS, IR and 1H NMR spectroscopy. The synthesized compounds were screened for their in …

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Studies Including Tolerance, Affinity And Capacity Of Certain Fungal Species For Some Toxic Elements In Aqueous Solution, A. Abdel-Razek, S. Mahmoud, H. El-Sheikh, T. Abdel-Ghany, M. Mahmoud Dec 2008

Studies Including Tolerance, Affinity And Capacity Of Certain Fungal Species For Some Toxic Elements In Aqueous Solution, A. Abdel-Razek, S. Mahmoud, H. El-Sheikh, T. Abdel-Ghany, M. Mahmoud

Al-Azhar Bulletin of Science

Some fungal species isolated from the soil of the radioactive repository site at HotLaboratoriesCenter were investigated for their tolerance, affinity and capacity towards different metal ions namely; Cerium Ce(III), Chromium Cr(VI), Cobalt Co(II), and Cadmium Cd(II). They were identified as Aspergillus tamarii, Aspergillus niger, Penicellium chrysogenum, Cunninghamella elegans and Rhizopus stolonifer. The obtained results showed that, the lowest concentration of metal ion could be tolerated by fungal species was 50ppm for Co(II) & Cd(II) , while the highest one was 2000ppm for Cr(VI) & Ce(III). Also, tolerance towards mixture of ions was varied among the fungi under study. The affinity …

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Cobalt(Ii) Complex Binding With Copolymer As A Proficient Catalyst For Oxidation Of Catechol, Ahmed Hanafy Dec 2008

Cobalt(Ii) Complex Binding With Copolymer As A Proficient Catalyst For Oxidation Of Catechol, Ahmed Hanafy

Al-Azhar Bulletin of Science

The metallopolymer cobalt(II) complex of a simple pyridine- and amide-containing copolymer (CoII-P9) was prepared and characterized with IR and 1H NMR. The 1H NMR spectrum of the copolymer indicates that the average repeating unit of the copolymer P9 is vinyl pyridine:acrylamide = 5:1. The IR spectra suggest that cobalt is bound to the polymer through the pyridine nitrogen atom and the acrylamide does not participate in the binding. The oxidation of catechol by CoII-P9 in the presence of 7.5 mM H2O2 exhibits enzyme-like pre-equilibrium kinetics, yielding kcat = 0.026 ± 0.3 s–1, dissociation constant K′ = 1.9 ± 0.6 mM, …

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Purification And Extraction Of Polysaccharide Specific Of Streptococcus Pyogenes Of Group A Fixing On Latex Particles, Ahmed Atia, Hussein El-Kabbani Dec 2008

Purification And Extraction Of Polysaccharide Specific Of Streptococcus Pyogenes Of Group A Fixing On Latex Particles, Ahmed Atia, Hussein El-Kabbani

Al-Azhar Bulletin of Science

The Streptococci are widely distributed in nature and frequently form part of the normal human flora which are members. Approximately 5-15% of humans carry Streptococcus pyogenes. Cytoplasmic membrane has antigens similar to those of human cardiac and heart valve fibroblasts. Patients may also develop immune- mediated such as acute rheumatic fever skin infections and endocarditis. S. pyogenes evolved anenzyme that specifically target IgG use as biochemical reactions, and serologic specificity. Serologic grouping is based on antigenic differences in cell wall carbohydrates (groupA). A technique for detection of antibodies against S. pyogenesgroup antigen / type antigens is being devised as one …

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Effect Of Cyclosporin-A As An Immunosuppressive Drug On Islet Cells Transplantation In Mice, Ashraf Seida, Mahmoud Gabr, Gabr Ezz El-Gamal, Hassan Ibrahim, Mohamed El-Gharib Dec 2008

Effect Of Cyclosporin-A As An Immunosuppressive Drug On Islet Cells Transplantation In Mice, Ashraf Seida, Mahmoud Gabr, Gabr Ezz El-Gamal, Hassan Ibrahim, Mohamed El-Gharib

Al-Azhar Bulletin of Science

Transplantation of normal isolated islets of langerhans for the treatment of diabetes remains an elusive goal in clinical practice. Perhaps the major problem preventing clinical islet transplantation has been limited by the inability to prevent islet allograft or xenograft rejection. Cyclosporin A is an immunosuppressive agent that improves survival of transplant. This exciting immunosuppressive agent was first used clinically in renal transplantation in 1978 (Ferguson and Fidlus 1982).The aim of this study was the isolation , purification and transplantation of hamster pancreatic islet as xenograft transplantation for the treatment of diabetic mice. It is also aimed to study the effect …

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Synthesis And Reactivity Of 2-[1-(5-Bromobenzofuran-2-Yl)-Ethylidene]Malononitrile In Synthesis Of Heterocyclic Systems;A Convenient Route For Synthesis Of Some Pyrazole, Thiophene, Thienopyrimidine, Isobenzofuran And Benzene Derivatives Incorporating Benzofuran Moiety, Mahmoud Abdelall, Ahmad Bedair, Fawzy Ali, Ahmad El-Agrody, Ahmad Halawa Dec 2008

Synthesis And Reactivity Of 2-[1-(5-Bromobenzofuran-2-Yl)-Ethylidene]Malononitrile In Synthesis Of Heterocyclic Systems;A Convenient Route For Synthesis Of Some Pyrazole, Thiophene, Thienopyrimidine, Isobenzofuran And Benzene Derivatives Incorporating Benzofuran Moiety, Mahmoud Abdelall, Ahmad Bedair, Fawzy Ali, Ahmad El-Agrody, Ahmad Halawa

Al-Azhar Bulletin of Science

A facile route to some pyrazole, thiophene, thienopyrimidine, phthalic anhydride and benzene derivatives incorporating benzofuran moiety is reported.

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Synthesis And Fungicidal Activity Of New Thiazole Derivatives Were Prepared From 2-Bromo-1-(3,4-Dimethylphenyl)Ethanone, Mahmoud Bashandy, Mahmoud Abdelall, Ahmed El-Morsy Dec 2008

Synthesis And Fungicidal Activity Of New Thiazole Derivatives Were Prepared From 2-Bromo-1-(3,4-Dimethylphenyl)Ethanone, Mahmoud Bashandy, Mahmoud Abdelall, Ahmed El-Morsy

Al-Azhar Bulletin of Science

2-bromo-1-(3,4-dimethylphenyl)ethanone (2) was prepared and converted to thiazole derivatives (6-11a-c, 14-20) through reactions with different reagents. Compounds (3, 5, 12, 13, 21) were prepared from reaction of compound (2) with 2-mercapto-4,6-dimethylnicotinonitrile1H-benzo[d]imidazole-2-thiol, p-chloroaniline, potassium cyanide and 2-aminobenzenethiol respectively. The synthesized compounds were confirmed by elemental analysis, IR, 1H-NMR and mass spectral analysis.

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Extrusion Of Sulfur In The Reactions Of Hydrazine Hydrate With 5-(2-Aryl-2-Oxoethylidene)-3-(2-Methoxy-Phenyl)-2-Thioxothiazolidin-4-Ones, Nadia El-Aasar Dec 2008

Extrusion Of Sulfur In The Reactions Of Hydrazine Hydrate With 5-(2-Aryl-2-Oxoethylidene)-3-(2-Methoxy-Phenyl)-2-Thioxothiazolidin-4-Ones, Nadia El-Aasar

Al-Azhar Bulletin of Science

Reactions of 3-substituted-5-(2-aryl-2-oxoethylidene)-2-thioxothiazolidin-4-ones 2a, b with 2.5 equiv. of hydrazine hydrate were carried out with reflux and/or at room temperature. Both of these conditions gave 4-(3-aryl-4,5-dihydro-1H-pyrazole-5-carbonyl)-4-(2-methoxyphenyl)thiosemicarbazides 3a, b and4-(2-methoxyphenyl) thiosemicarbazide 4. Inaddition, the 6-(2-oxo-2-phenylethyl)-4-(2-methoxyphenyl)-3-thioxo-1,2,4-triazinan-5-one 5a was obtained from 2a.The successful isolation of sulfur from these reactions was the key to rationalize the above mentioned transformations. The structures of all the products were evidenced by microanalytical and spectral data.

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Study On Thiazolopyridines Part (7) : Synthesis Of Novel Thiazolidinone And Thiazolo[3,2-A]Pyridine Derivatives, Gameel Elhag Ali, Hessen Altamamy, Shaaban Mohamed, Zamzam Basher Dec 2008

Study On Thiazolopyridines Part (7) : Synthesis Of Novel Thiazolidinone And Thiazolo[3,2-A]Pyridine Derivatives, Gameel Elhag Ali, Hessen Altamamy, Shaaban Mohamed, Zamzam Basher

Al-Azhar Bulletin of Science

A novel 2-ethoxycarbonyl methylidine-4,5-dihydo-4-oxo-5-arylmethylidine-1,3-thiazole derivatives (2a-c) are obtained via the reaction of 4-thiazolinone derivative (1) with different aromatic aldehydes. Cyclization of 4-thiazolidinone derivatives (2a-c) with various α–cyanocinnamonitriles afforded the corresponding thiazolopyridine derivatives (5a-r). Thiazolopyridine derivatives (5a,b ) are refluxed with acetic anhydride, and gave N,N-diacetyl amino derivatives (8a,b).

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The Feasibility Of Using Tantalum Metal As Indicator Electrode In Precipitation Titration Reactions, Enas Attia Dec 2008

The Feasibility Of Using Tantalum Metal As Indicator Electrode In Precipitation Titration Reactions, Enas Attia

Al-Azhar Bulletin of Science

Tantalum metalwas found to serve as an excellent indicator for potentiometric precipitation titrations. The experimental results were discussed in terms of the potential arrests and potential shifts upon addition of the titrant. The obtained results for 0.05M halogen solutions revealed that when tantalum electrode is coupled with SCE or Pt electrodes, sharp potential jumps and distinct end points were obtained in the titration of Clֿ, Brֿ and Iֿ solutions against 0.057M AgNO3 solution in both forward and backward titration techniques. On the other hand, Ta/Ag systems in forward titrations of Brֿ and Clֿ solutions behave similarly. While in backward titration, …

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Synthesis Of 4-Hydroxy-3-Substituted Coumarins Of Expected Biological Activity And Their Reactions With Some Nucleophiles, Nahed Abd El-Ghaffar, Nadia Dawood, Fatma Abd El-Salam, Awtif Farrag Dec 2008

Synthesis Of 4-Hydroxy-3-Substituted Coumarins Of Expected Biological Activity And Their Reactions With Some Nucleophiles, Nahed Abd El-Ghaffar, Nadia Dawood, Fatma Abd El-Salam, Awtif Farrag

Al-Azhar Bulletin of Science

3-Acetyl-4-hydroxy substituted coumarins (IIa-c) were prepared. Their reactions with hydrazines in DMF gave the corresponding 4-hydroxy -(3-substituted pyrazolin-3-yl)coumarins (IVa-f) via the intermediate hydrazone (III). Their reaction with hydroxylamine hydrochloride gave the corresponding isoxazol-3-yl coumarin (VIa-c) and (VIIa,b) via the oxime intermediate (V). Reaction of II with aromatic aldehydes gave the corresponding chalcone derivatives (VIIIa-k) which were reacted with hydrazines and hydroxyl amine hydrochloride and gave (IXa) and (Xa-c). Condensation of (IIa-c)with aromatic aldehydes, malononitrilein the presence ammonium acetate yielded the corresponding 3-cyano-4-aryl nictoinamido-6-yl-coumarin (XIa-f). 4-Hydroxy comumarin (1a-c) on treatment with POCl3 in DMF give the corresponding 4-Chloro-3-formyl coumarin (XIIa-c) which …

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Electroless Deposition Of Ni-Co-P, Ni-W-P And Ni-Co-W-P And Evaluation Of Their Corrosion Resistance., O. Khalifa, E. Abd El-Wahab, A. Tilp Dec 2008

Electroless Deposition Of Ni-Co-P, Ni-W-P And Ni-Co-W-P And Evaluation Of Their Corrosion Resistance., O. Khalifa, E. Abd El-Wahab, A. Tilp

Al-Azhar Bulletin of Science

2-Aminopyridine was fused with ethyl acetoacetate for two hours to yield the N-2- pyridyl–3-oxobutanamide (1). However, when the reaction time was increased to 5 hours compound 3 was obtained. Condensation of 3 with benzaldehyde gave 4. The reaction of pyridopyridone 3 with arylidenemalononitrile 7a-c afforded 4H-pyran derivatives 10a-c. In contrast to the behavior of arylidenemalononitriles 7a-c towards pyridopyridine 3, benzylidenemalononitrile 7d reacted with compound 3 to give the product 11. Compound 1 was allowed to react with arylidenemalononitriles to give the dihydropyridine derivatives 17a-d. Alkylation of compound 1 with alkylating agents has been also reported. Thus, compound 1 was condensed …

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Biodegradation Of Some Hydrocarbons In Suez Gulf Petroleum Crude Oil By Fusarium Oxysporum, M. Afifi, R. Bayoumi Dec 2008

Biodegradation Of Some Hydrocarbons In Suez Gulf Petroleum Crude Oil By Fusarium Oxysporum, M. Afifi, R. Bayoumi

Al-Azhar Bulletin of Science

Among fifty fungal isolates were isolated from crude oil polluted soil samples collected from different localities in Upper Egypt (Assuit), Fusarium oxysporum C61 was selected for crude oil biodegradation due to of its high metabolic activity. The identification process of fungal genera and species resulted in fifty fungal isolates belonging to twenty six genera presented as follows: ten strains of Aspergillus, nine strains of Penicillium and one strain of Absidia, Cunninghamella, Eupenicillium, Fusarium, Nectria, Phoma and Syncephallastrum. The influence of various, pH values, nitrogen sources, phosphrous sources, amino acids and vitamins were investigated to obtain optimal crude oil biodegradation. The …

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