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1.
2.
Chiral enolates 5 and 10 , generated by radical addition and subsequent reduction, show diastereofacial selectivity during protonation. In the presence of substituted amines, diastereoselectivity is enhanced and becomes comparable to radical stereoselection. Diastereoselectivities up to 99:1 and yields up to 90% are reached.  相似文献   
3.
In this study it was possible to measure the distribution of metoprolol, tramadol, and midazolam in human directly in several compartments. In the legal medicine autopsy material is normally investigated to find out the cause of death. But the results of corresponding toxicology measurements often involve more information. With screening methods drugs were detected without connection to the cause of death. The deceased had either a continual therapeutic treatment, a treatment during an operation, or an unsuccessful urgent therapy. A liquid/liquid extraction and a LC/MS/MS method were developed for the determination of the drug concentrations. Different autopsy materials of about 120 cases were investigated. Most frequently the drugs metoprolol, tramadol, and midazolam could be proved and determined simultaneously. Metoprolol was found in seven cases, tramadol in seven cases and midazolam in thirteen cases. The dosage of the drugs was unknown. Therefore and because of the low number of cases statistic calculations were not meaningful and an individual case study was necessary. In all cases with oral metoprolol application the patients probably took a normal customary continuous dosage. The concentrations of tramadol in blood were in the toxic range in three cases. The distribution of tramadol in the compartments was independent of the dosage. The time between oral intake of metoprolol or tramadol and death was unknown. With the distribution pattern of metoprolol in the compartments it was possible to estimate the duration between drug intake and death. In most cases midazolam was given intravenously during an operation or an unsuccessful urgent therapy. Sometimes the time between dosage and death was documented. The duration between application of the drug and death played the crucial role for the distribution of midazolam in the compartments. Measurements of drug concentrations in human autopsy material deepen the knowledge of the respective drugs' pharmacokinetics.  相似文献   
4.
With screening methods in the legal medicine drugs were often detected in autopsy material. In this study the antiarrhythmic and the local anesthetic drug lidocaine could be proved in fifty‐one cases and determined in different autopsy materials. For the first time the comparison of so many distribution patterns of lidocaine in human compartments was possible. A liquid‐liquid extraction procedure, a standard addition method and LC/MS/MS were used for analytics. The measured concentrations in blood were in the therapeutic range or lower. The time between lidocaine application and death was given in twenty‐nine cases. These data were very helpful to estimate and interpret the distribution process of lidocaine between application and death. This time exerted a crucial influence on the distribution of lidocaine in the compartments. Most of the intravenous applicated lidocaine was found in heart blood after a very short time of distribution. Afterwards the highest concentrations were measured in brain. Later the highest concentration was found in the kidney samples or in urine. If the time between lidocaine application and death is known, the results of this study can be used to deepen the knowledge of its pharmacokinetics. If this time is unknown, the circumstances and the causes of death can be better explained. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
5.
Magnetic properties at surfaces and interfaces have been investigated performing Perturbed Angular Correlation (PAC) measurements in the UHV chamber ASPIC (Apparatus for Surface Physics and Interfaces at CERN) using different PAC probes. The results are: (i) determination of magnetic hyperfine fields of Se on Fe, Co, Ni which are explained by a theoretical study on the magnetic hyperfine fields of 4sp-elements in adatom position on Ni and Fe;(ii) static magnetic hyperfine fields in ultrathin Pd on Ni(0 0 1) which indicate an induced magnetic order in Pd;(iii) the observation of induced fluctuating magnetic interactions in Pd when thick Pd is in contact with Ni. Monolayer-resolved measurements of the magnetic hyperfine fields in magnetized Pd are in accordance with theoretical predictions of the layer dependence of the induced magnetic moments in Pd. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
6.
We describe a mid-infrared Laser Magnetic Resonance (LMR) spectrometer which is based on a cryomagnet and a sealed-off CO-laser. Faraday rotation combined with a multireflection cell is used for polarization sensitive detection of molecular radical ions. Experimental details and first spectroscopic examples are given.  相似文献   
7.
Several new beta-delayed proton emitters have been observed at the on-line mass separator OASIS. They were provisionally identified as:125Ce (8.9±0.7 s),126pr (3.2±0.6 s),127Nd (1.9±0.4 s),128Nd (4±2 s),137Gd (7±3 s),139Gd (4.9±1 s), and143Dy (4.1±0.3 s).  相似文献   
8.
Large scale ab initio SCF and CI calculations are employed to study the potential curves for the d 3IIg, a 3IIu and X1Σ+g states of the C2 radical. The electronic transition moment Re′e″ for the Swan bands (d 3IIga 3IIu) is calculated in various AO and MO basis sets as a function of the internuclear CC distance. The form of the Σ|Re′e″|2 curve is in very good agreement with that obtained recently from measurements of Danylewych and Nicholls and Tatarczyk et al.; the calculated value for Σ|Re′e″2 at 2.44 bohr is found to be 5.2 au2 compared to the most recent experimental values of |Re(roo)|2 = 3.57 au2 of Tatarczyk et al.  相似文献   
9.
In [5], King proved that the centralizer of a rank-1 transformation equals the “weak closure” of its (positive and negative) powers (see below for a definition of the weak topology). We define rank-1 flows, and then show that simple modifications of King's proof yield an analogous statement for rank-1 flows.  相似文献   
10.
The lifetimes and the magnetic moments of the two excited62Cu states at 40.84 and 390.19 keV are investigated by time differential perturbed angular distribution measurements of the delayedγ-rays following the nuclear reactions61Ni(d, n) and62Ni(p, n). The results are:τ=6.7±0.5 nsec,μ=1.32±0.03 n. m. for the 2+ state at 40.84 keV, andτ=16.0±0.3 nsec,μ=2.00±0.01 n. m. for the 3+ state at 390.19 keV.  相似文献   
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