116 research outputs found
A cooperative Pd-Cu system for direct C-H bond arylation
The authors are grateful to the Royal Society (University Research Fellowship to CSJC) for financial support.A novel and efficient method for C-H arylation using well-defined Pd- and Cu-NHC systems has been developed. This process promotes the challenging construction of C-C bonds from arenes or heteroarenes using aryl bromides and chlorides. Mechanistic studies show that [Cu(OH)(NHC)] plays a key role in the C-H activation and is involved in the transmetallation with the Pd-NHC co-catalyst.Publisher PDFPeer reviewe
Perception of Nuclear Energy and Coal in France and the Netherlands
This study focuses on the perception of large scale application of nuclear energy and coal in the Netherlands and France. The application of these energy-sources and the risks and benefits are judged differently by various group in society. In Europe, France has the highest density of nuclear power plants and the Netherlands has one of the lowest. In both countries scientists and social scientists completed a questionnaire assessing the perception of the large scale application of both energy sources. Furthermore, a number of variables relating to the socio cultural and political circumstances were measured. The results indicate that the French had a higher risk perception and a more negative attitude toward nuclear power than the Dutch. But they also assess the benefits of the use of nuclear power to be higher. Explanations for these differences are discussed
Neutral dinuclear copper(I)-NHC complexes : synthesis and application in the hydrosilylation of ketones
The authors gratefully acknowledge the Royal Society (University Research Fellowship to C.S.J.C.) for funding.The synthesis of a class of highly stable neutral dinuclear Cu(I)-NHC complexes using 1,2,4-triazole as a bridging ligand is described. Various NHCs were used to generate a library of [Cu(μ-trz)(NHC)]2, complexes. Interestingly, [Cu(μ-trz)(IPr)]2 was found to be highly active in the hydrosilylation of ketones, without the need for an external base or any other additive. A wide range of aryl and alkyl ketones, as well as sterically hindered ketones, was successfully reduced to alcohols using the lowest catalyst loading reported to date.PostprintPeer reviewe
Gender and Tahrir Square: contesting the state and imagining a new nation
This article argues that the concepts of ‘State’ and ‘Nation’ should be treated as separate from one another, hence, more than one image of the nation is possible at one given time. During the early days of the January 2011 Egyptian revolution, a contestation emerged between Mubarak’s state and the protesters in Tahrir Square over the image and notion of the Egyptian nation. Both the state and the protesters attempted to exclude one another from their respective discourse of the Egyptian nation. While reflecting back on a number of women’s voices who joined the early days of the Tahrir Square protests and using qualitative fieldwork interviews with Cairo-based feminist and political activists, this article points to the complexity of a newly forged image of Egyptian nationhood. In Tahrir Square, this image appeared to be largely framed within gendered criteria where notions of manhood and hyper visible gender equality were intrinsically linked to the broader objective of removing Mubarak and his regime. This raises the question of whether new gender paradigms of equality can continue to exist beyond Tahrir Square’s imagination of a ‘new’ nation
Marketing Practices For Dairy Products From Small-Scale Farms, Case: Region Of Tiziouzou – Algeria
The objective of our work is to identify the different marketing practices and to characterize the organizational constraints that hinder the productivity and profitability of small-scale livestock farms in the mountainous region of Fréha and Sidi-Naman, located in the region of Tizi-Ouzou, Algeria. Due to its high milk production potential, the targeted region was selected as a study area. The importance of our work lies in the determination of the key factors, which prevent small-scale milk producers from carrying out their livestock activities successfully. A quantitative questionnaire survey was conducted with 30 farmers
DAS MANAGEMENT DER ORDENTLICHEN AKTIEN
Common stocks are easier to describe than fixed-income securities such as bonds, but they are harder to analyse. Fixed-income securities almost always have a limited life and an upper kune limit on cash payments to investors.
Common stocks have neither. Although the basic principles of valuation apply to both, the role of uncertainty is larger for common stocks, so much so that it often dominates all other elements in their valuation.Iako se redovite dionice mogu lakše opisati od vrijednosnih papira koji nose fiksnu dobit dospijeća kao npr. dionice, teže ih je analizirati. Vrijednosni papiri fiksne dobiti gotovo uvijek imaju ograničeni vijek te gornju kunsku granicu za gotovinska plaćanja investitorima.
Redovite dionice nemaju niti jedno od ovih svojstava. Iako se temeljna načela vrednovanja primjenjuju na oba oblika, kod redovitih dionica je uloga nesigurnosti veća, tako da ona često dominiraju nad ostalim elementima vrednovanja.Es ist viel einfacher die ordentlichen Aktien zu beschreiben als die Wertpapiere mit dem fixen Fälligkeils gewinn wie z.B. Aktien, jedoch ist es schwieriger sie zu analysieren. Die Wertpapiere mit dem fixen Gewinn haben fast immer eine begrenzte Lebensdauer und die oberste Grenze der Kuna für die Barzahlungen an Investoren.
Die ordentlichen Aktien haben keine dieser Eigenschaft. Obwohl man die Grundprinzipien der Bewertung an beiden Formen anwendet ist bei den ordentlichen Aktien die Unsicherheitsrolle größer, sodaß sie oft über den anderen Bewertungselementen dominiert
Use of ring-expanded diamino- and diamidocarbene ligands in copper catalyzed azide-alkyne "click" reactions
The
two-coordinate ring-expanded N-heterocyclic carbene copper(I)
complexes [Cu(RE-NHC)<sub>2</sub>]<sup>+</sup> (RE-NHC = 6-Mes, 7-<i>o</i>-Tol, 7-Mes) have been prepared and shown to be effective
catalysts under neat conditions for the 1,3-dipolar cycloaddition
of alkynes and azides. In contrast, the cationic diamidocarbene analogue
[Cu(6-MesDAC)<sub>2</sub>]<sup>+</sup> and the neutral species [(6-MesDAC)CuCl]<sub>2</sub> and [(6-MesDAC)<sub>2</sub>(CuCl)<sub>3</sub>] show good
activity when the catalysis is performed on water
IDENTIFICATION OF KINEMATIC HARDENING THANKS TO MAGNETIC METHOD
International audienceMagnetic non destructive methods are widely used in the industries of steel since magnetic behavior demonstrates a good sensitivity to the microstructural and/or mechanical changes. It is well known that plastic deformations lead to a sharp degradation of the magnetic properties of ferromagnetic materials (strong decrease of susceptibility, increase of hysteresis losses) especially for weak plastic strain levels. Therefore, Magnetic method can be potentially used to evaluate the plastic state of a material. This evaluation requires an accurate model as principal part of the non destructive procedure. This model has to predict the magnetic behavior of the material involved. It must on the other hand demonstrate low computation time to allow "on line" inverse identification of the mechanical and metallurgical state. Such magneto-mechanical modeling is proposed. It is based on the so-called mul- tidomain model. Plasticity is introduced through internal stress characterizing heterogenous biphasic structure. Plastic deformation and kinematic hardening can be consequently estimated by magnetic measurements
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