Thick Walled Multiple Opening Reinforced Concrete Conduits

The Department of The Army Corps of Engineers, Engineering Division, Civil Works, Contract No. DACW-73-70-C-003

Allylic Amination and Carbon–carbon Double Bond Transposition Catalyzed by Cobalt(II) azodioxide Complexes

The unusual cobalt(II) diphenylazodioxide complex salts [Co(az)4](PF6)2 and [Co(bpy)(az)2](PF6)2 have been shown to catalyze the allylic amination/C–C double bond transposition reaction of 2-methyl-2-pentene with PhNHOH, with a turnover number of about 4. The mechanism is proposed to involve a nitroso-ene-like transfer of a PhNO moiety from the azodioxide ligand to the alkene, followed by reduction of the organic product to yield a cobalt(III) intermediate, which is itself reduced back to cobalt(II) by PhNHOH, regenerating PhNO. Hetero-Diels-Alder trapping experiments suggest that an “off-metal” mechanism, in which PhNO is released from the cobalt complexes and reacts with the alkenes, is operative, in contrast to an “on-metal” mechanism observed by Nicholas and coworkers for [Fe(az)3](FeCl4)2

Cobalt(II) Diphenylazodioxide Complexes Induce Apoptosis in SK-HEP-1 Cells

The cobalt(II) complex salts [Co(bpy)(az)2](PF6)2 and [Co(az)4](PF6), each bearing the unusual cis-N,N\u27-diphenylazodioxide ligand, were both screened as possible anticancer agents against SK-HEP-1 liver cancer cells. Both compounds were found to induce substantial apoptosis as an increasing function of concentration and time. Measurement of apoptosis-related proteins indicated that both the extrinsic and intrinsic pathways of apoptosis were activated. The apoptotic activity induced by these salts is not displayed either by simple cobalt(II) salts or complexes or by the free nitrosobenzene ligand. Additionally, these compounds did not induce apoptosis, as assessed by poly(adenosine diphosphate-ribose) polymerase cleavage, in several other cell lines

Cobalt(II) Diphenylazodioxide Complexes Induce Apoptosis in SK-HEP-1 Cells

The cobalt(II) complex salts [Co(bpy)(az)2](PF6)2 and [Co(az)4](PF6), each bearing the unusual cis-N,N\u27-diphenylazodioxide ligand, were both screened as possible anticancer agents against SK-HEP-1 liver cancer cells. Both compounds were found to induce substantial apoptosis as an increasing function of concentration and time. Measurement of apoptosis-related proteins indicated that both the extrinsic and intrinsic pathways of apoptosis were activated. The apoptotic activity induced by these salts is not displayed either by simple cobalt(II) salts or complexes or by the free nitrosobenzene ligand. Additionally, these compounds did not induce apoptosis, as assessed by poly(adenosine diphosphate-ribose) polymerase cleavage, in several other cell lines

Electrochemical Studies of Cobalt(II) diphenylazodioxide Complexes

The electrochemical behavior of the unusual cobalt(II) diphenylazodioxide complex salts [Co(az)4](PF6)2 1 and [Co(bpy)(az)2](PF6)2 2 has been studied by cyclic voltammetry. Each complex displays two quasireversible redox couples, which are proposed to correspond to a reduction of Co(II) to Co(I), followed by a ligand-based reduction. Irreversible reductions of 1 are observed at more negative potentials, and are proposed to arise from deposition of elemental Co and the decomposition of transiently formed Co(-I) species. Spectroelectrochemical experiments on both 1 and 2, involving electrolytic reduction followed by reoxidation, are consistent with the quasireversibility observed in the CV measurements

Camel breeding development project in Tunisia

Camel breeding is of great socio-economic importance in southern Tunisia. Although, the size of the national camel herd has decreased over the years from 120000 to 56000 heads in 2014. Illegal export, low breeding efficiency, social modernization and lack of investment are the major causes of this decline. To remedy this situation, the Tunisian government has established a national program for development and research on camel production. This program is based on grants to farmers to encourage rearing of replacement females and fattening camels; improvement of pastures and water infrastructure, promotion of applied research in specialized centers. Research eff orts are centered on health, nutrition and improvement of rangelands, development of reproductive biotechnologies and genetic improvement. An attempt was carried out to genotype the local breeds of camels. Development of semen preservation and artificial insemination has met several challenges inherent to the peculiarities of reproduction in this species

Projet de développement de l’élevage camelin en Tunisie

Camel breeding is of great socio-economic importance in southern Tunisia. Although, the size of the national camel herd has decreased over the years from 120 000 to 56 000 heads in 2014. Illegal export, low breeding efficiency, social modernization and lack of investment are the major causes of this decline. To remedy this situation, the Tunisian government has established a national program for development and research on camel production. This program is based on grants to farmers to encourage rearing of replacement females and fattening camels; improvement of pastures and water infrastructure, promotion of applied research in specialized centers. Research efforts are centered on health, nutrition and improvement of rangelands, development of reproductive biotechnologies and genetic improvement. An attempt was carried out to genotype the local breeds of camels. Development of semen preservation and artificial insemination has met several challenges inherent to the peculiarities of reproduction in this species. Keywords: Husbandry, reproduction, biotechnologies, Camel, TunisiaL’élevage du dromadaire joue un rôle socio-économique important dans le sud tunisien mais le nombre de dromadaires a connu ces dernières années une diminution importante de 120 000 à 56 000 en 2014. L’exportation illégale, le rendement faible de l’élevage, la modernisation de la vie des personnes et le manque d’investissement dans ce domaine sont les principales causes de cette diminution. Pour remédier à ce problème, l’état tunisien a proposé un programme national de développement et de recherche dans le domaine du dromadaire basé sur (1) l’encouragement des éleveurs par la subvention de l’élevage des femelles de remplacement et l’engraissement des chamelons, (2) l’amélioration des infrastructures dans les pâturages; notamment l’aménagement des points d’eau pour les animaux et (3) la promotion de la recherche appliquée dans les centres spécialisés. Les principaux thèmes de recherche sont axés sur la santé animale, l’alimentation des dromadaires et l’amélioration des zones de parcours, l’insémination artificielle et le transfert d’embryon et la sélection génétique des animaux. Dans le domaine de la biotechnologie de la reproduction, des essais ont été réalisés dans le typage génétique des dromadaires, la conservation du liquide séminal et l’insémination artificielle pour surmonter les difficultés particulières de la reproduction chez le dromadaire. Mots-clés: Élevage, reproduction, biotechnologies, dromadaire, Tunisi

RETRATO SIN IDENTIFICAR [Material gráfico]

Copia digital. Madrid : Ministerio de Educación, Cultura y Deporte, 201

Synthesis and Characterization of Cobalt(II) N,N′‑Diphenylazodioxide Complexes

Removal of chloride from CoCl2 with TlPF6 in acetonitrile, followed by addition of excess nitrosobenzene, yielded the eight-coordinate cobalt(II) complex salt [Co{Ph(O)NN(O)- Ph}4](PF6)2, shown by single-crystal X-ray analysis to have a distorted tetragonal geometry. The analogous treatment of the bipyridyl complex Co(bpy)Cl2 yielded the mixed-ligand cobalt(II) complex salt [Co(bpy){Ph(O)NN(O)Ph}2](PF6)2, whose singlecrystal X-ray structure displays a trigonal prismatic geometry, similar to that of the iron(II) cation in the previously known complex salt [Fe{Ph(O)NN(O)Ph}3](FeCl4)2. The use of TlPF6 to generate solvated metal complex cations from chloride salts or chlorido complexes, followed by the addition of nitrosobenzene, is shown to be a useful synthetic strategy for the preparation of azodioxide complex cations with the noncoordinating, diamagnetic PF6 − counteranion. Coordination number appears to be more important than d electron count in determining the geometry and metal−ligand bond distances of diphenylazodioxide complexes