122 resultados para Deutschland <bis 1945>


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In this work, we address the thermal properties of selected members of a
homologous series of alkyltriethylammonium bisf(trifluoromethyl)sulfonylgimide ionic
liquids. Their phase and glass transition behavior, as well as their standard isobaric heat
capacities at 298.15 K, were studied using differential scanning calorimetry (DSC),
whereas their decomposition temperature was determined by thermal gravimetry analysis.
DSC was further used to measure standard molar heat capacities of the studied ionic liquids
and standard molar heat capacity as a function of temperature for hexyltriethylammonium,
octyltriethylammonium, and dodecyltriethylammonium bisf(trifluoromethyl)sulfonylgimide
ionic liquids. Based on the data obtained, we discuss the influence of the alkyl chain
length of the cation on the studied ionic liquids on the measured properties. Using viscosity
data obtained in a previous work, the liquid fragility of the ionic liquids is then discussed.
Viscosity data were correlated by the VTF equation using a robust regression along a
gnostic influence function. In this way, more reliable VTF model parameters were obtained than in our previous work and a good estimate of the liquid fragility of the ionic liquids was made.

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Hexa-n-butylditin is prepared in high yield (83%), by reduction of bis(tri-n-butyltin) oxide with sodium borohydride in ethanol. The first stage is reduction. to tri-n-butyltin hydride (not isolated), which rapidly gives hexa-n-butylditin with the Loss of hydrogen under the basic reaction conditions.

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The Ni-II centre in the cation of the title compound, [Ni(C6H12S3)(2)]Br-2. 4H(2)O, occupies a crystallographic inversion centre and is octahedrally coordinated by six S-donors from two [9]aneS(3) ligands. Ni-S distances range from 2.3749 (16) to 2.4077 (15) Angstrom and S-Ni-S angles where both thia donors belong to the same ligand lie in a narrow range between 88.09 (5) and 88.67 (6)degrees. The water molecules participate in extensive hydrogen bonding with each other and with the Br- anions to form double chains with eight- and 12-membered hydrogen-bonded rings running along the crystallographic a direction.

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pp. 181-204

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Herein, we present a comparative study of the thermophysical properties of two homologous ionic liquids, namely, trimethyl-sulfonium bis[(trifluoromethyl) sulfonyl]imide, [S111][TFSI], and trimethyl-ammonium bis[(trifluoromethyl)sulfonyl]imide, [HN111][TFSI], and their mixtures with propylene carbonate, acetonitrile, or gamma butyrolactone as a function of temperature and composition. The influence of solvent addition on the viscosity, conductivity, and thermal properties of IL solutions was studied as a function of the solvent mole fraction from the maximum solubility of IL, xs, in each solvent to the pure solvent. In this case, xs is the composition corresponding to the maximum salt solubility in each liquid solvent at a given temperature from 258.15 to 353.15 K. The effect of temperature on the transport properties of each binary mixture was then investigated by fitting the experimental data using Arrhenius' law and the Vogel-Tamman-Fulcher (VTF) equation. The experimental data shows that the residual conductivity at low temperature, e.g., 263.15 K, of each binary mixture is exceptionally high. For example, conductivity values up to 35 and 42 mS·cm-1 were observed in the case of the [S 111][TFSI] + ACN and [HN111][TFSI] + ACN binary mixtures, respectively. Subsequently, a theoretical approach based on the conductivity and on the viscosity of electrolytes was formulated by treating the migration of ions as a dynamical process governed by ion-ion and solvent-ion interactions. Within this model, viscosity data sets were first analyzed using the Jones-Dole equation. Using this theoretical approach, excellent agreement was obtained between the experimental and calculated conductivities for the binary mixtures investigated at 298.15 K as a function of the composition up to the maximum solubility of the IL. Finally, the thermal characterization of the IL solutions, using DSC measurements, showed a number of features corresponding to different solid-solid phase transitions, TS-S, with extremely low melting entropies, indicating a strong organizational structure by easy rotation of methyl group. These ILs can be classified as plastic crystal materials and are promising as ambient-temperature solid electrolytes. © 2013 American Chemical Society.

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Featuring a brand new examination of Islamic fundamentalism in the wake of the Arab Spring, this fully revised and updated second edition of Islamic Fundamentalism since 1945 analyzes the roots and emergence of Islamic movements in the modern world and the main thinkers that inspired them.

Providing a much-needed historical overview of a fast-changing socio-political landscape, the main facets of Islamic fundamentalism are put in a global context, with a thematic debate of issues such as:

- the effects of colonialism on Islam

- secularism and the Islamic reaction

- Islam and violence in the 9/11 era

- globalization and transnational Islamist movements

- Islam in the wake of the Arab Awakening

Islamic Fundamentalism since 1945 provides an authoritative account of the causes and diversity of Islamic fundamentalism, a modern phenomenon which has grabbed the headlines as a grave threat to the West and a potentially revolutionary trend in the Middle East. It is a valuable resource for students and those interested in the history, effects and consequences of these Islamic movements

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This third edition of Conflicts in the Middle East since 1945 analyzes the nature of conflict in the Middle East, with its racial, ethnic, political, cultural, religious and economic factors. Throughout the book Peter Hinchcliffe and Beverley Milton-Edwards put the main conflicts into their wider context, with thematic debates on issues such as the emergence of radical Islam, the resolution of conflicts, diplomacy and peace-making, and the role of the superpowers.

The book is brought fully up to date with events in the Middle East, covering, for instance, developments in Iraq in 2006 where a democratically elected government is in place but the insurgency show no sign of coming under control. The analysis of the Palestinian/Israeli conflict is also brought up to the present day, to include the election of the Hamas government and the 2006 conflict between Israel and Lebanon’s Hizballah.

Including a newly updated bibliography and maps of the area, this is the perfect introduction for all students wishing to understand the complex situation in the Middle East, in its historical context.

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Infolge steigender Lebenserwartung sowie sinkender Geburtenraten wird das Durchschnittsalter der Bevölkerung in den meisten Industrienationen in den kommenden 50 Jahren stark ansteigen. Zur gleichen Zeit scheidet nach wie vor die Mehrzahl älterer Arbeitnehmer vor Erreichen der gesetzlichen Altersgrenze aus dem Arbeitsmarkt aus. Dies hat sowohl negative Auswirkungen auf die Finanzierbarkeit sozialer Sicherungssysteme als auch langfristig auf die Verfügbarkeit qualifizierter Arbeitnehmer am Arbeitsmarkt. Nationale Regierungen verfolgen daher gegenwärtig verschiedene Maßnahmen mit dem Ziel, die Arbeitsmarktbeteiligung älterer Arbeitnehmer zu erhöhen (OECD 2006). Diese Maßnahmen werden jedoch zum Teil durch die Strategien des betrieblichen Personalmanagements konterkariert, die oft noch jugendzentristisch ausgeprägt sind und ältere Mitarbeiter bei Einstellung, Beförderung, Weiterbildung sowie bei Arbeitsplatz- und Arbeitszeitgestaltung direkt oder indirekt benachteiligen (Bellmann et al. 2003).

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The Behavioural Inhibition and Behavioural Activation System (BIS/BAS) scales were developed by Carver and White (1994) and comprise four scales which measure individual differences in personality (Gray 1982, 1991). More recent modifications, namely the five-factor model derived from Gray and McNaughton's (2000) revised Reward Sensitivity Theory (RST) suggests that Anxiety and Fear are separable components of inhibition. This study employed exploratory and confirmatory factor analyses on the scales in order to test whether the four or five-factor model was the better fit in a sample of 994 participants aged 11–30 years. Consistent with RST, superior model fit was shown for the five-factor model with all variables correlated. Significant age effects were observed for BIS Fear and BIS Anxiety, with scores peaking in middle and late adolescence respectively. The BAS subscales showed differential effects of age group. Significantly increasing scores from early to mid and from mid to late adolescence were found for Drive, but the effect of age on Fun Seeking and Reward Responsiveness was not significant.



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Mutations in the Ras-pathway occur in 40–45% of colorectal cancer patients and these are refractory to treatment with anti-EGFR-targeted therapies. With this in mind, we have studied novel guanidinium- based compounds with demonstrated ability to inhibit protein kinases. We have performed docking stud- ies with several proteins involved in the Ras-pathway and evaluated 3,40-bis-guanidinium derivatives as inhibitors of B-Raf. Compound 3, the most potent in this series, demonstrated strong cytotoxicity in WTB-Raf colorectal cancer cells and also cells with V600EB-Raf mutations. Cell death was induced by apop- tosis, detected by cleavage of PARP. Compound 3 also potently inhibited ERK1/2 signalling, inhibited EGFR activation, as well as Src, STAT3 and AKT phosphorylation. Mechanistically, compound 3 did not inhibit ATP binding to B-Raf, but direct assay of B-Raf activity was inhibited in vitro. Summarizing, we have identified a novel B-Raf type-III inhibitor that exhibits potent cellular cytotoxicity