Ein Verfahren zur Trennung des Zinks von allen Metallen seiner Gruppe

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Micro raman spectroscopy on a single carbon fibre under stress

An example is given for the application of Raman spectroscopy in material characterization. Raman spectra of carbonaceous materials obtained with the microscope attachment have been used to study orientation of graphite planes in a single carbon fibre under stress with a lateral resolution of 1 m.Dedicated to Professor Dr. H. Kriegsmann on the occasion of his 70th birthday     

Heterobimetallic Cuprates Consisting of a Redox‐Switchable,Silicon‐Based Metalloligand: Synthesis,Structures, and Electronic Properties

A series of bimetallic silyl halido cuprates consisting of the new tripodal silicon‐based metalloligand [κ³N‐Si(3,5‐Me₂pz)₃Mo(CO)₃]^? is presented (pz=pyrazolyl). This metalloligand is straightforwardly accessible by reacting the ambidentate ligand tris(3,5‐dimethylpyrazolyl)silanide ({Si(3,5‐Me₂pz)₃}^?) with [Mo(CO)₃(η⁶‐toluene)]. The compound features a fac‐coordinated tripodal chelating ligand and an outward pointing, “free” pyramidal silyl donor, which is easily accessible for a secondary coordination to other metal centers. Several bimetallic silyl halido cuprates of the general formula [CuX{μ‐κ¹Si:κ³N‐Si(3,5‐Me₂pz)₃Mo(CO)₃}]^? (X=Cl, Br, I) have been synthesized. The electronic and structural properties of these complexes were probed in detail by X‐ray diffraction analysis, electrospray mass spectrometry, infrared‐induced multiphoton dissociation studies, cyclic voltammetry, spectroelectrochemistry, gas‐phase photoelectron spectroscopy, as well as UV/Vis and fluorescence spectroscopy. The heterobimetallic complexes contain linear two‐coordinate copper(I) entities with the shortest silicon–copper distances reported so far. Oxidation of the anionic complexes in methylene chloride and acetonitrile solutions at ${E{{0\hfill \atop 1/2\hfill}}}$ =?0.60 and ?0.44 V (vs. ferrocene/ferrocenium (Fc/Fc⁺)), respectively, shows substantial reversibility. Based on various results obtained from different characterization methods, as well as density functional theory calculations, these oxidation events were attributed to the Mo⁰/Mo^I redox couple.     

Ueber die Bestimmung des Wismuths in Silberraffinirschlacke

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Aequivalentgewicht des Kupfers

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Zur Bestimmung des Schwefels in Handels- und Werkbleien

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Polyacrylamide gel electrophoretic studies on the self-association of crotamine: characterization and molecular dimension of n-mer species

Polyacrylamide gel electrophoresis (PAGE) at pH 4.4 was used to study the concentration dependence of absolute mobility of crotamine. Within amounts ranging from 5-65 micrograms the toxin appeared in at least three n-mer species which were characterized by their geometrical mean radius R and molecular weight Mr estimation. The R and Mr values of crotamine bands were obtained from equations described in the literature and by using standard polypeptides and proteins submitted to the same experimental conditions. When amounts of up to 20 micrograms were assayed by PAGE the bands had a monomer molecular weight value of 4650 and R was 1.08 nm. From 20-35 micrograms the toxin migrated as dimer (Mr 10,000) with an R value of 1.42 nm. However, amounts higher than 35 micrograms crotamine were mostly resolved in a "two-band" pattern with R and Mr values corresponding to higher associated species.