Magnetic relaxation of 3He-B after a large tipping pulse

A time dependent precession frequency is observed in ³He-B after a large tipping pulse (>104°) in transverse NMR. Relating the frequency to the tipping angle reveals the time dependence of the longitudinal magnetization. A fit of Fomin's theory to the data yields the Leggett-Takagi collision time at various temperatures.     

The vanishing viscosity as a selection principle for the Euler equations: The case of 3D shear flow

We show that for a certain family of initial data, there exist non-unique weak solutions to the 3D incompressible Euler equations satisfying the weak energy inequality, whereas the weak limit of every sequence of Leray–Hopf weak solutions for the Navier–Stokes equations, with the same initial data, and as the viscosity tends to zero, is uniquely determined and equals the shear flow solution of the Euler equations corresponding to this initial data. This simple example suggests that, also in more general situations, the vanishing viscosity limit of the Navier–Stokes equations could serve as a uniqueness criterion for weak solutions of the Euler equations.     

Inviscid symmetry breaking with non-increasing energy

In a recent article, C. Bardos et al. constructed weak solutions of the three-dimensional incompressible Euler equations which emerge from two-dimensional initial data yet become fully three-dimensional at positive times. They asked whether such symmetry-breaking solutions could also be constructed under the additional condition that they should have non-increasing energy. In this note, we give a positive answer to this question and show that such a construction is possible for a large class of initial data. We use convex integration techniques as developed by De Lellis and Székelyhidi.     

Determination of naltrexone and 6β-naltrexol in human blood: comparison of high-performance liquid chromatography with spectrophotometric and tandem-mass-spectrometric detection

We present data for a comparison of a liquid-chromatographic method coupled with tandem mass spectrometry (LC-MS/MS) and a high-performance liquid-chromatographic method with column switching and UV spectrophotometric detection. The two methods were developed for determination of naltrexone and 6β-naltrexol in blood serum or plasma aiming to be used for therapeutic drug monitoring to guide the treatment of patients with naltrexone. For the high-performance liquid chromatography (HPLC)/UV detection, online sample cleanup was conducted on Perfect Bond C₁₈ material with 2% (vol/vol) acetonitrile in deionized water. Drugs were separated on a C₁₈ column using 11.5% (vol/vol) acetonitrile and 0.4% (vol/vol) N,N,N,N-tetramethylethylenediamine within 20 min. LC-MS/MS used naltrexone-d ₃ and 6β-naltrexol-d ₄ as internal standards. After protein precipitation, the chromatographic separation was performed on a C₁₈ column by applying a methanol gradient (5–100%, vol/vol) with 0.1% formic acid over 9.5 min. The HPLC/UV method was found to be linear for concentrations ranging from 2 to 100 ng/ml, with a regression correlation coefficient of r ²?>?0.998 for naltrexone and 6β-naltrexol. The limit of quantification was 2 ng/ml for naltrexone and 6β-naltrexol. For the LC-MS/MS method the calibration curves were linear (r²?>?0.999) from 0.5 to 200 ng/ml for both substances, and the limit of quantification was 0.5 ng/ml. The concentrations measured by the two methods correlated significantly for both substances (r²?>?0.967; p?<?0.001). Both methods could be used for therapeutic drug monitoring. The HPLC/UV method was advantageous regarding automatization and costs, whereas LC-MS/MS was superior with regard to sensitivity.     

Nanostructured all-solid-state supercapacitors based on NASICON-type Li1.4Al0.4Ti1.6(PO4)3 electrolyte

Journal of Solid State Electrochemistry - Lithium aluminum titanium phosphate (LATP), a NASICON-type (structure of Na1 + xZr2SixP3 − xO12,...     

Distinction of Original and Forged Lithographs by Means of Thermogravimetry and Raman Spectroscopy

Thermal analysis has been used to study the composition of paper and paper-like materials for some decades. The application of these techniques permits to distinguish between the original paper which was used by the artists and possible forgeries. Quite often, however, the identification of the differences demands the simultaneous application of several other techniques. The present investigation includes Asiatic wood-prints from China and Japan, and lithographs of European artists, such as Pablo Picasso, Salvador Dali, and Marc Chagall. Utamaro (1753–1806) is one of the most celebrated artists in the history of the Japanese woodblock print. He became one of the famous painters of ‘Ukiyo-e’ (Ukiyo-e means transitory world). In China Utamaro's pictures were also produced. The differences are found in the kind of paper: The Japanese used Mitsumata paper, while the Chinese printed on Bamboo paper mixed with silk fibers. Hu-jü-zong (Nanking, 1619) and a group of famous Chinese painters created the book of the ‘Ten Bamboo Studio’ which contains woodblock prints as visual aids for young artists. A reprint of these woodblock prints appeared in 1717. Later, a bootleg of this book appeared in Japan (1817). The differentiation is possible by thermogravimetric investigation of the used papers. Statistic evaluations in Europe show that more than 1 000 000 bootleg copies of lithographs of Pablo Picasso, Salvador Dali, and Marc Chagall exist. Thermoanalytical measurements allow the distinction between the original artifacts and the bootlegs. Raman spectroscopy gives an additional possibility for the distinction between the applied color pigments. This revised version was published online in July 2006 with corrections to the Cover Date.     

Der Spannungszustand einer quadratischen Platte mit quadratischer Öffnung

Ohne Zusammenfassung