293 research outputs found
A half-century of metal and metalloid-containing polymers
No full textAlaa S. Abd-El-Aziz ... [et al.]; Includes bibliographical references and indexes.; Editor, Alaa S. Abd-El-Aziz, is currently President of the University of Prince Edward Island.Source type: Electronic(1
Dibenzyl ferrocene-1,1′-dicarboxylate
No full textIn the title compound, [Fe(C13H11O2)2], there are markedly different orientations of the two phenylmethoxycarbonyl substituents [O—C—C—C torsion angles = 84.5 (3) and 139.6 (2)°]. These orientations are mediated by a number of intermolecular C—H...O interactions, which result in a one-dimensional hydrogen-bonded network of molecules
Pobreza y sexo en "La colmena" de Camilo José Cela y "El edificio Yacobian" de Alaa Al-Aswany
No full textThe purpose of this article is to analyze and compare the novel by the Spanish writer Camilo José Cela and the Egyptian author Alaa al-Aswany, emphasizing the features of poverty and sex in the two novels: La colmena (1951) and The Yacobian building (2002). We also highlight the causes and circumstances that led some characters to resort to sex as their only alternative and escape route in one society as in the other. Therefore, this research work approach both the Spanish and the Egyptian reality to which the author refers.Este trabajo de investigación consiste en el análisis y la comparación de la novela del escritor español Camilo José Cela y el egipcio Alaa al-Aswany haciendo hincapié en los rasgos de pobreza y sexo en las dos novelas: La colmena (1951) y El edificio Yacobian (2002). También subrayamos las causas y circunstancias que llevaron a algunos personajes en recurrir al sexo como su única alternativa y vía de escape tanto en una sociedad como en la otra. Por ello, la investigación aborda tanto la realidad española como la egipcia a la que se refiere el autor
Questions éthiques en gestion de crise. Observations québécoises et défis égyptiens
No full textCet article présente, dans une première partie, les fondements éthiques de la gestion de crise qui s’apparentent au pragmatisme et à l’écologie humaniste et s’appliquent dans une approche systémique axée sur l’apprentissage et le dialogue. Dans une deuxième partie, il discute de quelques questions éthiques dans le domaine de la sécurité civile en s’appuyant principalement sur les observations empiriques de l’auteur au Québec. Dans le cadre de sa mission en tant que boursier du Programme canadien de bourses de la Francophonie, l’auteur termine par un examen des défis culturels relatifs à son aspiration d’établir une éthique et une culture de gestion de crise dans son pays, l’Égypte.In the first section, this article presents the ethical foundations of crisis management whose origins emanate from pragmatism and humanistic ecology and are applied in a systemic approach based on learning and dialogue. In the second section, it examines some ethical issues in the field of civil security by referring mainly to the author’s empirical observations in Quebec. As an Egyptian scholar of the Programme canadien de bourses de la Francophonie, the author concludes by discussing the cultural challenges related to his aspirations to establish a crisis management ethic and culture in Egypt
Poverty and sex in La Colmena by Camilo José Cela and The Yacobian building by Alaa Al-Aswany
No full textThe purpose of this article is to analyze and compare the novel by the Spanish writer Camilo José Cela and the Egyptian author Alaa al-Aswany, emphasizing the features of poverty and sex in the two novels: La colmena (1951) and The Yacobian building (2002). We also highlight the causes and circumstances that led some characters to resort to sex as their only alternative and escape route in one society as in the other. Therefore, this research work approach both the Spanish and the Egyptian reality to which the author refersEste trabajo de investigación consiste en el análisis y la comparación de la novela del escritor español Camilo José Cela y el egipcio Alaa al-Aswany haciendo hincapié en los rasgos de pobreza y sexo en las dos novelas: La colmena (1951) y El edificio Yacobian (2002). También subrayamos las causas y circunstancias que llevaron a algunos personajes en recurrir al sexo como su única alternativa y vía de escape tanto en una sociedad como en la otra. Por ello, la investigación aborda tanto la realidad española como la egipcia a la que se refiere el auto
Oil spill monitoring using satellite imagery in the Sharm El-Maya Bay of Sharm El-Sheikh, Egypt
No full textSharm el-Sheikh, in Egypt, is a prominent tourist destination. The city attracts millions of visitors annually due to its exceptional location and pleasant climate. Owing to its natural ecosystem and marine diversity, Sharm El-Maya Bay in Sharm el-Sheikh attracts beachgoers and vacationers. In 1999, however, an oil spill occurred at the site. Previous investigations detected a network of buried steel pipelines and a number of buried reinforced concrete tanks, both of which may have contributed to the contamination problem. Although the problem is so detrimental to health and the environment, no follow-up studies were conducted after 2013. Therefore, the author chose to monitor oil leaks over the headland using frequent, high-resolution Google Earth Pro remote sensing data for the years 2017 to 2022. To disclose whether any corrective measures were taken to address the contamination problem. Moreover, to demonstrate if any unanticipated variations have occurred over many years due to climatic factors. The elucidation of the aforementioned issues demonstrates Google Earth Pro's effectiveness in monitoring pollution problems. The results revealed that the area and perimeter of four oil spots had changed slightly over time. During the specified time period, the standard deviations of the four monitored locations fluctuated between 111.1 m2, 71.6 m2, 83.7 m2, and 254.3 m2. The research proved that the pollution problem has not improved over time because stakeholders have not reacted. In addition, it highlighted the uniqueness of Google Earth Pro in tracking the changes in oil spot size over a time series
The effect of some dentin bonding agents on Dycal lining cement
No full textDentin primer is applied as a routine procedure prior to bonding to improve the sealing properties of direct polymerizing
resins. Some primers contain acetone or alcohol that may affect the properties of calcium hydroxide liner which is placed as
a direct or indirect pulp capping. If calcium hydroxide is softened or smeared over the cavity walls, the bonding will be impaired.
Therefore, the cement must be removed, the walls must be cleansed and the procedure must be repeated with careful application
of dentin primer. The purpose of this study was to determine the wear and compressive strength of a calcium hydroxide liner
(Dycal) after exposure to different kinds of dentin primers for different periods of time. Dycal was mixed according to the
manufacturer’s instructions and placed in plastic rings of 0.5 mm x 5 mm and allowed to set at 37°C for 15 minutes under 500
gm load. To determine erosion, the height for each sample before and after application of primers was recorded using Digital
Height Measuring Instrument (Digmar 817). Compressive strength specimens were also prepared. Dycal treated with Optibond
or Syntac for 1 minute or 5 minutes had the highest erosion values and the lowest compressive strength values. Gluma CPs (water
based primer) had the least effect on Dycal.Corresponding Author:
Dr. Alaa El-Araby
Department of Restorative Dental Sciences
College of Dentistry, King Saud University, P.O. Box 60169, Riyadh 11545, KSA
Email: [email protected]
Organometallic polymers of arenes coordinated to group VI and VIII transition metals
No full textThis review focuses on the synthesis and properties of organometallic polymers of arenes coordinated to transition metals of groups VI and VIII. This category of polymers includes systems where the metallic moiety is coordinated to the arenes prior to, or following polymn. Nucleophilic arom. substitution of transition metal complexed haloarenes with various di-nucleophiles gave rise to polymeric materials with pendent metallic moieties. Condensation reactions of monomer complexes with org. reagents were employed in the synthesis of these materials. An alternative approach to the formation of organometallic polymers is via coordination of metallic moieties to the arom. backbone of purely org. polymers. The polymeric materials with pendent metallic moieties generally exhibited an increase in soly. relative to their org. analogs. Some of these polymers have also displayed interesting electrochem. and optical properties
Journal of inorganic and organometallic polymers and materials: Special issue dedicated to Didier Astruc
No full textCopyright (C) 2012 American Chemical Society (ACS). All Rights Reserved.; Section Code: 35-1Source type: Electronic(1
A brief overview of the structural determination of cyclopentadienyliron arene complexes.
No full textA review, with ∼9 refs., of the use of NMR spectroscopy for the detn. of the structure of a no. of cyclopentadienyliron arene systems. The examples presented here demonstrate the use of 1- and 2-dimensional NMR techniques in predicting the chem. structure and dynamics of these complexes. The numerous isomers obtained from the hydride addn. to mono- and dicyclopentadienyliron arene complexes were identified using 2-dimensional HH COSY and CH COSY. The 2-dimensional 1H COSY, DQ-COSY and NOE study of the ((η6-2,6-dimethylphenyl)(phenylsulfonyl)acetonitrile)-η5-cyclopentadienyliron cation showed that there is restricted rotation about the arene-methine C bond. 1-Dimensional NMR was also used for the detn. of the diastereomeric nature of the arene complexes, which arose from their complexation to the cyclopentadienyliron moieties, as well as in estg. the no. of repeating units in the oligomeric complexes
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