Investigation on the effectiveness of the repair method 8.3 “Corrosion protection by increasing the electrical resistivity” in chloride-containing concrete Part 2: Chloride redistribution in concrete after application of a system sealing surface protective coating

This DFG-funded research project aimed to gain a better understanding of the mechanisms of the W-Cl repair principle within the framework of fundamental investigations, to contribute to the creation of the necessary basis for a broader application of the repair principle in practice. The focus was on the development of a model to describe the chloride redistribution after the application of a system sealing surface protective coating. On the basis of Fick's second law of diffusion, a mathematical model with a self-contained analytical solution was developed, with the help of which the chloride redistribution after application of a system sealing surface protective coating can be calculated under the idealized assumption of complete water saturation of the concrete. Furthermore, the influence of the dehydration of the concrete, expected as a result of the application of the repair principle W-Cl, on the chloride redistribution was investigated. On the basis of laboratory tests and numerical simulations, material-specific reduction functions were developed to quantify the relationship between the chloride diffusion coefficient and the ambient humidity.     

Selective Analysis of Sulfur-Containing Species in a Heavy Crude Oil by Deuterium Labeling Reactions and Ultrahigh Resolution Mass Spectrometry

A heavy crude oil has been treated with deuterated alkylating reagents (CD₃I and C₂D₅I) and directly analyzed without any prior fractionation and chromatographic separation by high-field Orbitrap Fourier Transform Mass Spectrometry (FTMS) and Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) using electrospray ionization (ESI). The reaction of a polycyclic aromatic sulfur heterocycles (PASHs) dibenzothiophene (DBT), in the presence of silver tetrafluoroborate (AgBF₄) with ethyl iodide (C₂H₅I) in anhydrous dichloroethane (DCE) was optimized as a sample reaction to study heavy crude oil mixtures, and the reaction yield was monitored and determined by proton nuclear magnetic resonance spectroscopy (¹H-NMR). The obtained conditions were then applied to a mixture of standard aromatic CH-, N-, O- and S-containing compounds and then a heavy crude oil, and only sulfur-containing compounds were selectively alkylated. The deuterium labeled alkylating reagents, iodomethane-d₃ (CD₃I) and iodoethane-d₅ (C₂D₅I), were employed to the alkylation of heavy crude oil to selectively differentiate the tagged sulfur species from the original crude oil.     

一体化的信号源分析仪

与美国同行争分夺秒抢占市场先机不同,欧洲测量仪器厂商Rohde&Schwarz公司的产品策略则相对稳健,他们的产品更专注于功能的多样化     

Analyses of rhythms of the body temperature in free running in rats

The objective of this study was to determine the disturbances of urea in serum and urine of endurance trained volunteers during prolonged exposure to hypokinesia (decreased number of km/day). The studies during hypokinesia (HK) were performed for 364 days on twenty long-distance runners in the age of 23 to 26 years, with an average peak oxygen uptake, of 66 ml.kg.min-1. All volunteers were divided into two equal groups: Ten volunteers were placed on a continuous regime of exercise 14.8 km/day and served as control subjects (CS). The remaining volunteers were subjected to continuous HK without the use of any preventive measures and were considered as the hypokinetic subjects (HS). For the simulation of the hypokinetic effect, the HS were kept continuously under an average of 2.7 km/day for the duration of the study. Prior to exposure to HK, the HS were on the same exercise regime as the CS. During a 60 day pre-HK period and during the experimental period, urinary excretion of urea, creatinine, sodium, potassium and calcium and concentrations thereof in serum were measured. In the HS the concentrations of urea, creatinine, sodium, potassium and calcium in serum and the rate of excretion thereof in urine increased significantly when compared to the CS. It was concluded that prolonged restriction of muscular activity induces significant disturbances of urea in serum and urine of endurance trained volunteers.     

Zur Verantwortung des Informatikers-Militärische Anwendungen der Informatik

Ohne Zusammenfassung     

Bauarten von Kristallisatoren

Types of crystallizers . In the industrial application of single mass crystallization from solution clear aims exist with regard to crystallizate qualities. To fulfil these aims, one can choose between various types of crystallizers. Magma types, i.e. agitated tank crystallizer, forced circulation and draft tube (baffle) crystallizer, as well as classifying types with the well-known Oslo-crystallizer belong to the present state of the art. The rates of secondary nucleation decrease in the same sequence as that given above and the possibilities of influencing crystal size distributions increase, and coarser crystals are produceable.