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- 360 degree Feedback (1)
- Assessment Center (1)
- Carboxylate (1)
- Case-Study (1)
- Evidence-based Management (1)
- Leadership Competencies (1)
- Modular Augmented Launcher (1)
- N,N,O Ligands (1)
- N,N′ Ligands (1)
- Zinc (1)
We argue that effective leadership development should be evidence-based, i.e. that it combines the best available scientific evidence with
research in the specific organizational context. To illustrate our proposition, we report findings from a case study in a multinational organization. The goal was to examine which rater source in the company’s 360 degree feedback would provide the most valid information about leadership competencies. Therefore, we explored relationships between 360 degree ratings and assessment center (AC) ratings of the same leadership competencies (N=151). It was predicted that AC ratings show higher overlap with 360 degree ratings for behaviors that specific rating
sources can more easily observe in the ratees’ work life. Results showed that peers were the most accurate observers of leadership competencies in 360 degree assessments, compared to managers and subordinates. This corroborates our argument for an evidence-based instead of an
intuitive handling of 360 degree feedback results. Practical implications and avenues for future research are discussed.
The adsorption and reaction of the amino acid glycine (NH2-CH2-COOH) are studied experimentally on the polar single crystal surface of zinc oxide, ZnO(000-1), by X-ray photoelectron spectroscopy (XPS) under UV light in presence and absence of molecular O2. Deposition at 350 K mainly resulted in a largely deprotonatedmonolayer (NH2-CH2-COO−(a)+OH(s); where O is surface oxygen,(a)is for adsorbed and(s)is for surface species) identified by its XPS C1s binding energy at 289.3 eV (-COO), 286.7 eV (-CH2-) and XPS O1s at 531.8 eV(-COO). A decrease in the signals of all functional groups of the adsorbed glycine (monitored by their C1s, O1s,and N1s lines) is seen upon UV excitation in the absence and presence of O2pressures up to 5 × 10−6 mbar. The photoreaction cross sections extracted from the decrease in the C1s peaks were found to be =2.6 × 10−18(COO(a)) and 1.4 × 10−18(-CH2-)cm^2. The photoactivity of the ZnO(000-1) surface under UHV-conditions is found to be comparable to that seen in direct photolysis of amino acids in solution.
To achieve high temperature stable insulation materials for the electrical insulation of fine copper wires two different bis(alkoxysilylalkyl)pyromellitamide acids 1 and 2 were prepared. These organic–inorganic sol–gel hybrid precursors were obtained via reactions of pyromellitic dianhydride and alkoxysilylalkylamines. The molecular single-source precursors 1 and 2 were comprehensively studied using FT-IR, 1H, 13C and 29Si NMR spectroscopy as well as elemental analyses. Besides, the hydrolysis and condensation processes of the different precursors were examined with solution 29Si NMR spectroscopy. The imidization process was investigated using 13C NMR spectroscopy, FT-IR spectroscopy as well as thermal analysis methods. The different precursors were applied to coat fine copper wires using an industrial coating device. The obtained coatings were cured at temperatures between 380 and 425 °C, and tested regarding thicknesses, number of pinholes, electrical breakdown voltage and elongation. FT-IR spectroscopy was used to determine the chemical structure and scanning electron microscopy to investigate the morphology of the coating materials. The obtained coatings showed very promising mechanical, thermal and electrical properties, i.e. highest breakdown voltage values well above 200 V/µm. They possess high flexibility without cracking and no pinholes or other defects were detected.
Three dinuclear zinc carboxylate complexes [L1−3Zn(μ,η2-O2CPh)]2 (1, 2, 4) containing either the bidentate N,N′-chelating β-diketiminate ligand RNC(Me)C(H)C(Me)NR (R = 2,6-iPr2-C6H3, L1, complex 1), the tridentate O,N,N-chelating ligand OC(Me)C(H)C(Me)NCH2CH2NMe2 (L2, complex 2) or the bis-N,N′-chelating bis-β-diketiminate ligand RNC(Me)C(H)C(Me)NNC(Me)C(H)C(Me)NR (R = 2,6-iPr2-C6H3, L3, complex 4) were synthesized and characterized including single-crystal X-ray diffraction. Reaction of the neutral bis-β-diketimine (L3(H)2) with two equivalents of ZnMe2 leads to the expected heteroleptic dinuclear zinc complex L3(ZnMe)2 3 in 93 % yield. Further reaction with benzoic acid PhCO2H leads to complex 4. Complex 2 forms a rather strong carboxylate-bridged dimer, whereas the carboxylate groups in complexes 1 and 4 act as asymmetrical bridges between both Zn atoms, pointing to the formation of a weakly bonded dimer. The zinc atoms in 1 and 4 are tetrahedrally coordinated, whereas in 2 the coordination number is increased to five due to the coordination of the pendant donor arm. The ring opening polymerization (ROP) of rac-lactide was investigated with the zinc complexes 1–4 and diazabicycloundec-7-ene (DBU) as a co-catalyst. Complexes 2 and 3 are active polymerization catalysts, which in the presence of DBU converted 200 equiv. of rac-lactide into polylactide within 10 min at ambient temperature. The analysis of the crude polymer showed that the lactide polymerization with catalyst 2 occurs via a slightly modified activated-monomer mechanism.